WHY is my first shot high?


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docsleepy
April 7, 2013, 03:44 PM
My "cold" first shot on a 7mm08 Savage is consistently 2" higher than the group that follows, beginning with the 2nd shot. It is very notable, as the groups (4 or 5 shots beginning with the 2nd shot) will be around 1".

Handloads, 42 grains Varget, 120 grain spire point Sierra, if any of that is important. I'm using a Rock BR front rest, and leather rear bag, using a wooden shim around the rounded forearm so that the rifle slides just like my 6PPC benchrest gun, which achieves in the range of 3/8" groups. The action is bedded. The lug is precision.

It is ALWAYS verticle stringing. The horizontal spread of all the shots is virtually always within 1". The first shot is just high.

I've tried shooting it uncleaned.
I've tried shooting it minimally cleaned.
I've tried shooting it extensively cleaned and de-coppered.

They are always high.

I can go up or down 1 or 2 grains of powder and I don't get near that change in verticle point of impact.

WHY? Can anyone give me a explanation for WHY that first shot is HIGH rather than LOW or RIGHT or LEFT?

I have a Mosin Nagant that is now down to 1" groups and its first shot is dead on. My benchrest 6PPC with a Shilen stainless match barrel - first shot is identical to others. My AR15 and AR10 -- no difference in first shot.

Any ideas?

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NeuseRvrRat
April 7, 2013, 03:45 PM
it's not unusual for the cold bore shot to have a different POI

docsleepy
April 7, 2013, 03:53 PM
Here is a representative group, where the 1st shot was actually 3" high. In this case the outside temperature was 65 degrees and the rifle uncleaned. On a warmer day (75 F) with a decoppered bore, the first shot was more like 1.5" high. Statistically these might be identical.

docsleepy
April 7, 2013, 03:55 PM
but why? why high? and not low? or right? or anything? All the other shots are grouped reasonably well. If it is powder, why doesn't the uncleaned bore shoot the same cold? If it is temperature, why don't the 3rd 4th and 5th shots move farther?

MErl
April 7, 2013, 04:03 PM
You say you tried cleaning or not and it didnt change this.
How about a quick cleaning after every shot?
Have you tried shooting a group and letting it sit untouched for an hour to get back to 'cold bore' temperatures? would it string again.

A guess, something is shifting in transport and storage which gets reset on that first shot. A little imperfection in the bedding or scope mount, possibly even the scope itself? That is just a guess though, you probably know more about it than I do.

docsleepy
April 7, 2013, 04:05 PM
When I waited an hour, it shot at the top of the bottom group, but not nearly as high as the first shot. Your thought about something changing in transport is intriguing. I wondered about sharply banging the butt of the stock on my foot or the ground.

docsleepy
April 7, 2013, 04:06 PM
I could try a different scope.

dvdcrr
April 7, 2013, 04:22 PM
For safety I would never get in the practice of sharply banging a gun on the ground. One day if you forget a round in the chamber you could end up blowing your head off. What I would is sight in using a slow five shot group. Center that group on your point of aim and " draw a fine bead" always on your first shot unless its way out there then aim dead center. I know you are wondering why and I don't know why but if the overall group is small and well zeroed it doesnt matter especially if you practice a lot and know where your gun shoots. Also let a couple buddies shoot it and see if it does the same for them. It might not be the gun, maybe after the first shot you are snugging up tighter to the gun or something.

kBob
April 8, 2013, 07:27 AM
In a class I took from EJ Land, he warned that the first shot from a cold barrel will seldom go where the following shots go and had us shoot from cold bores several times. He insisted this was one of the reasons a good shooter keeps records in a journal, so you can predict this and take it into account when that first shot has to count.

Oddly if a many times national champion and world famous sniper thinks this is a common event that one should take into account and I see it demonstrated time and again I tend to think it is normal

Consider for a moment that many competitions allow for a "fouling shot" or two before the scored portion of the relay. What does that tell you?

Any changes in condition can change POI. Dropping the rifle should cause one to expect a change in POI......and drop and give me fifty.... and one for Mom.....and one for the Ranger in the Big Blue Sky.....etc.

-kBob

Caliper_RWVA
April 8, 2013, 11:06 AM
How are the rounds being fed into the chamber? Do you load all five into the mag and feed from there or single load?

ironworkerwill
April 8, 2013, 11:11 AM
You may be on the right track. I would suspect the scope first. However, just like barrel harmonics the scope will experience vibrations when shot. Also saying you get more vertical stringing from a cold bore with that load. I may just be a load development issue. I started using Re 17 in my 7mm-08 and have seen groups shrink. Using 45gns of H414 and 130 grn sie mkings and 2+'' to 45.2gns of Re17 and 160grn gkings with 1.25'' groups. I expected more recoil from the latter but seen it to be noticably milder. Go figure that one.

drcook
April 8, 2013, 11:21 AM
If you all watch the shows on the Military Channel that documents the US military's precision shooter (ie: sniper) contests, you would see that one of the competitions is the "cold bore" shoot.

Military precision shooters are taught to find out where the cold bore shot goes, because that is typically what their first shot is.

Having the first shot go into somewhere different is not a fault of the gun, nor of the scope, nor of the shooter. It is just a fact of life concerning metals and firearms.

Even my BPCR rifles shooting lead cast bullets and black powder and weighing almost 15lbs due to their barrel size don't shoot the first shot where the rest of them go.

Col. Plink
April 8, 2013, 11:34 AM
I think I can echo what's been said, mainly with respect to coldbore shots. They are largely unpredictable versus the following shots, but if you get predictable coldbore POI that's a good thing (predictable!).

In terms of cleaning cylcles, a seasoned distance shooter described to me how many times shooters will never really isolate a problem with accuracy because they change more than one variable at a time.

He recommends taking a log of performance from a cold, clean barrel going forward. As the initial fouling takes place, the groups will tighten-up until the fouling begins to force them back out again. The sweet spot lies somewhere in between a clean, cold barrel and an over-fouled one. You can conceivably do a light cleaning (no de-coppering) and keep the sweet spot longer, until the copper fouling starts to take over.

Basically, if small variances in accuracy are really a problem, a full-process approach to logging shot info and cleaning frequency is the way to go.

Float Pilot
April 8, 2013, 03:34 PM
1. try another scope as mentioned.

2. Try only cold bore shots.

3. Make sure the rounds in the magazine are not having their COL changed by the recoil. ( bullets being pushed in or out of the case slightly while banging around in the magazine)

4. Try single load vs magazine load.

5. CHECK THE TORQUE on your action screws.

6. You might have a pressure point in your fore-arm channel of the stock that seats better after recoil or when it gets a little warmer. You can sometimes wedge a business card between the stock channel and barrel and get some interesting results.

7. Remember that some powder is Temp sensitive and if a cartridge sits in a hot chamber for 10 seconds the powder is now a hundred or more degrees warmer than the first shot's powder.

docsleepy
April 8, 2013, 08:58 PM
Thanks guys for all these ideas!

1. I always individually hand load each shot; I don't use the magazine.
2. I have been keeping records for years. I started the "cold bore" records on this gun after the last work I did on it and picked this up.
3. I think the barrel is not fully free floated -- I will work on that. THis may have a change during first/second shots due to mechanical changes.
4. Just bugs me that my $130 Mosin Nagant does NOT have this problem.

I'll report back.

Thanks!

The-Reaver
April 8, 2013, 09:00 PM
Dunno, aim two inches low when it counts

nathan
April 8, 2013, 09:04 PM
Locktite those mounting screws.

Kachok
April 8, 2013, 09:09 PM
Had a similar glitch with a Savage, my brother somehow managed to twist the stock until it was pushing against the barrel, don't know how he did it but I shimmed some folded paper between then pushing the stock out and left it for a week, problem solved.

chaser_2332
April 8, 2013, 10:07 PM
It's just your cold bore, learn it and compensate for it. Some guns are worse than other. As long as its repeatable whats the problem. Adjust your scope for the cold bore then back for the following shots, shouldn't be an issue. Alot of matches have a cold bore shot for this very reason. It's all about knowing your rifle and scope.

Andrew Leigh
April 9, 2013, 02:40 AM
Not discounting the effect of the cold bore throwing the first round off, one must not discount other possible causes.

Vertical stringing is indicative of poor breathing control and can also be diagnostic of a broken / malfunctioning firing pin.

jim243
April 9, 2013, 02:53 AM
Locktite those mounting screws.

As you heat up the barrel and chamber the metal will swell to give a tighter fit to the stock, some times this can be corrected by making sure the mounting screws are tourked correctly.

Jim

BluegrassDan
April 9, 2013, 06:35 AM
Torque wrench. I would suspect the front action screw or the scope mounts. Most likely tge front action screw.

docsleepy
April 9, 2013, 10:03 PM
OK. Here's an update.

I removed the stock and used sandpaper on PVC pipe to create enough clearance to guarantee that it was completely free floated.

In the process I verified that the actions WERE tight, and they HAD BEEN Loctited.

The bedding looked perfect. There was a tiny spec of epoxy jutting out from the stock just in FRONT of where the barrel lug would be; I knocked that off. I also added some epoxy to the forearm to perhaps make it a tiny bit stiffer.

I decided to put a tiny dab of RTV clear on the rear of the barrel lug (where it will contact the bedding). I also installed a small bit of RTV on the outside of the action screws where there are no threads (to make them snug in all directions) and loctited the recesses of the action threads. Put it all back together.

Created annealed, full length sized, then neck sized, 42 grain Varget, 120 grain Sierra SP ammo as always. The COAL was selected after several tests of grouping.

Pounded the butt on the ground a couple of times firmly but not destructively before placing rifle in the Rock BR front rest, and leather rear rest. As always, verified good fore n aft movement of the rifle in the bench rest, locked down the front rest before each shot. 16X scope, able to keep the cross hairs still on the target with less than 1/4" observable error in sighting, parallax removed with AO. Bore was NOT cleaned since last session couple days ago. 100 yard target.

As expected, the zero had shifted slightly due to all this taking off / putting back on. The first shot was 2" higher than the 2nd shot, and then the 3rd and 4th were touching/on top of each other one inch further down and slightly more leftward. I readjusted the scope based on the last shots, and the next shot was perfect. I proceeded to hit 3 out of 3 4" clay pigeons at 215 yards on the berm. No misses. Of course, there was no way to do another "cold shot" so that testing was done for the day.

This weekend I may have a chance to try it again, and see if the new zero is holding and whether the cold shot is still repeatably high or not.

fdashes
April 9, 2013, 10:13 PM
Could be very simple reason and fix. Marksman know all about the first shot from a cold barrel and many preach the "fouling" shot. It may be caused by a too clean barrel. Are you cleaning the rifle between each and every range visit. Try not cleaning the rifle on a return trip and see if that does it for you.

BCRider
April 9, 2013, 10:15 PM
I'll bet that if you log the temperature of the barrel through the seasons you'll find that the cold bore elevation change varies with temperature as well. On a hot summer day if the gun sits in the sun for a while there may not be much shift at all. But on a cool day you'll likely get this much or more until it warms up.

An hour SHOULD be long enough to cool off but what if it's sunny that day and you had the gun sitting protected from wind and in the sun? That could prevent it cooling off that far.

You may want to add a column to your cold bore log which is for "barrel metal temperature". Log that and the elevation changes for "cold bore" and I would not be surprised if you don't get a repeatable pattern to emerge. Of course you'll need to find something to measure the metal's temperature accurately.

BluegrassDan
April 10, 2013, 06:52 AM
How long do you wait between shots?

ball3006
April 10, 2013, 11:23 AM
Because you don't flinch on your first shot.....chris3

docsleepy
April 10, 2013, 08:53 PM
Hi guys, I did not clean the bore before this round.

Metal temperature is a possibility, although the data that I've gotten so far doesn't seem to support it. Not much difference between days of widely varying temperatures

I don't really think that I have any Flinch. The gun is fully in a benchrest. My other guns are Mosin-Nagant's. With either, I can hit clay pigeons at 200 yards reliably. What is odd to me is that the Mosin-Nagant, highly modified, does not have the cold barrel effect at all. Nor does my 6PPC.

I usually wait one or two minutes between shots. These rounds are each hand loaded into the chamber.

docsleepy
April 11, 2013, 07:02 AM
I have two scopes on order, whenever they arrive I will switch the scope.

chaser_2332
April 11, 2013, 12:22 PM
Your overthinking the problem, if its repeatable whats the issue. Compensate an go on with it.

c.latrans
April 11, 2013, 01:52 PM
Not that this helps your cause, but I am watching this thread like a hawk because I have a rifle that has done the same thing for 15 years. I love the gun so I have kept it and have tried every trick you have mentioned plus a few and NOTHING makes a difference. First shot of the day out of a cold/clean/fouled/dirty to the point of cruddy bbl.....every time that first shot is 4 inches straight high, then every time following shots drop right where desired and make pretty round groups. I have learned to cope with it, but it took me YEARS to trust the fact that I needed to adjust for the first shot. That is normally the one that counts, and it took a long time for me to be comfortable holding 12 inches low on a 300 yard shot. Its counter intuitive, but it works for me. Good luck, let us know if you figure it out!

BCRider
April 11, 2013, 02:08 PM
I worked with a fella that was on a SWAT team at one point in his police career. The scopes on their long distance precision guns were always set for that all important cold bore first shot. It was the followup shot where they relied on the mil dots or "Kentucky elevation" to adjust.

DRYHUMOR
April 12, 2013, 05:24 AM
I have some rifles that put cold bore shots where I aim, a couple that don't, depending on ammunition charge, bullet, clean barrel etc.

As a primer ignites and fires the bullet it creates a harmonic through the steel of the barrel. The cold steel or clean cold steel will react differently than after the first shot.

Like some had said, if your rifle puts the first round consistently high, but centered, you can either compensate for it or ignore it. Most of my first shots through a clean cold bore, I aim off target as to me it is a fouler. Unless in a hunting situation, in which case I compensate by holding where I expect the cold bore shot to go.

benEzra
April 12, 2013, 10:06 AM
If you have a chrono, you might try seeing if the velocity is consistent between the first shot and subsequent shots, too, just to rule that out as a factor.

docsleepy
April 12, 2013, 11:12 AM
I might be able to Chrono it. What I need to know, is how many hours have to pass, before the shot will move back up. That would be important in an all day hunting trip.

Eyesac
April 12, 2013, 07:06 PM
Try pouring cold water on it to get it back to cold bore temps (something I've wanted to try for a while but haven't gotten around to). And if it works, let me know, cause you could get some cold bore work done in an hurry...

docsleepy
April 15, 2013, 05:58 PM
OK, here is the first, second and third shots after changing out scope to identical 4-16X scope. These are done at 50 yards (the farthest I dared attempting boresighted shots). Visually boresighted and let 'er rip.

New scope with ring screws loctited.
Front rest identical Rock BR.
Used some of remaining batch of annealed, full length sized, handloaded rounds.
Rear Rest identical
Position held steady well within 1/4", firm hold as usual for this firearm.
Barrel dirty, not cleaned since last shots, outside temp approx 80 F or hotter, done in shade as usual.
Didn't think to chrono (sorry!)

First shot is obviously high (remember this is 50 yards not 100 as previous).
2nd and Third shots are right on each other.

So I'm beginning to wonder if the threads on the barrel are shifting or something with the first shot. This is a stock standard Savage receiver, never blueprinted.

Abel
April 16, 2013, 06:29 AM
A candidate for rebarrel!

docsleepy
April 16, 2013, 09:14 AM
Yes, I think a shilen.

Today ill try to chrono first and following shots. Wonder if the rifling has a bend or something else odd.

Orkan
April 16, 2013, 09:25 AM
it's not unusual for the cold bore shot to have a different POI It's unusual for a rifle that doesn't need a gunsmith's attention.

docsleepy
April 16, 2013, 12:19 PM
Orkan -- did you have any suggestions?

I've ordered a Shilen, Chrome-moly match, blued
7m08 standard chamber (I neck down .308 cases so I'll have about .004" total clearance, which will be reasonable for a hunting rifle/target rifle)
22" total length (selected to maximize stiffness, and the sporter was 22")
S8 Bull Barrel (just like my 6PPC). 1.05 all the way
9" twist (which will allow for heavier bullets or slower speeds)
Standard Shank.

The last Shilen I got went onto my 6PPC and although it is not a world-beater, it was absolutely reliable.

I'll try to chrono today, dunno if it will work, because I have to get the FIRST SHOT.

ford8nr
April 16, 2013, 12:32 PM
You say the rifle is shot out of a rest front and rear. Does it do the same if you shoulder the gun and shoot it off a front bag? I'm thinking the rest might shift on the first shot then settle in for the test. Repeatability word be odd though.

jerkface11
April 16, 2013, 12:37 PM
Wait 5 minutes between shots. With the rifle kept upright with the bolt open.

Float Pilot
April 16, 2013, 04:55 PM
My featherweight M-70 did that... Eventually I glass bedded the entire action and barrel channel. Now it does the first three shots into one hole and then they start to wander due to barrel heating.

U.S.SFC_RET
April 16, 2013, 06:12 PM
Whenever I qualified with a Rifle in the Army the first round was always off. It's not unusual.

docsleepy
April 16, 2013, 06:13 PM
fordnr -- It will be more difficult to spot if shouldered, as overall accuracy declines somewhat.

As you can see from some of the groups, firing every 2 minutes gives touching shots....so barrel heating is a minimal effect.

This rifle was bedded, and I rechecked it recently.

docsleepy
April 16, 2013, 06:41 PM
Here's my data from today.
Much hotter in Florida, 85 deg F. GNATS!!!!


As you can see, once again the first shot of high, this case by 1 inch.
The 3rd shot is the low one, I can't explain that.
There are nine shots total and as you can see, the rifle groups pretty well when it is not the 1st shot. The 2nd shot is somewhere in that glob of holes.

VELOCITIES: I dont' have the diffusers, so my chrony is very picky. It malfunctioned on most shots.

1st shot was 2914 fps
4th shot was 2902 fps (in the glob)
8th shot was 2992 (in the glob)
9th shot was 3023 (not sure where it went)

So yes, the first shot is somewhat slower. If that held up, I might could have some rounds with 1 extra grain of powder?

But the shilen barrel is on order now. 9" twist, bull barrel, 22" (short, thick), chrome-moly.

Oh -- one commenter wondered if my rifle "settles" in the rear bag after the first shot. I would consider that a possibilty -- except I do NOT see this with my 6PPC in the exact same front/rear rest.

Orkan
April 16, 2013, 07:01 PM
Orkan -- did you have any suggestions?
Sorry for the abrupt answer. It was more to combat the idea that it's perfectly acceptable for the "cold bore" shot to be outside of the group. I don't believe it to be acceptable at all, and every rifle that I've owned which exhibited that behavior was rectified by handing it to a qualified gunsmith and working the problem together.

The important thing to do is log this behavior, if you aren't already. Then subsequently log any action applied to rectify it. By this method you can close in on the problem through the process of elimination. It helps to have other highly qualified shooters at your disposal during this process in order to eliminate yourself as a variable.

Personally, I would pop the barrel off and true up the action. If I'm removing the barrel and truing the action, then it also holds true that I'm putting a new barrel on. If those two things are happening, then it might warrant a new bedding job as well. Any rifle I've had which was exhibiting the symptoms you have documented here, was wearing a factory barrel. Upon rebarreling/truing/bedding... the problem no longer existed. As a result, it's very difficult for me to be able to point at a single root cause. I rarely expend any effort "forcing" a factory tube to shoot. If it doesn't shoot, it gets ripped off and I don't think for a second about it.

I'm sorry if that's not much help, but you may find it to be a reality of your situation. I am thankful that you're documenting your experiences here though... because I believe that when you solve it, you will have effectively proven that no one should be forced to live with a cold bore shot that drops any differently than the rest. :)

docsleepy
April 16, 2013, 08:27 PM
Orkan -- I suspect strongly that you're right.

Since I'm not made of money, I go at things a little bit on a smaller scale. The only action that I've ever had trued, was a Savage action that shot well before it was trued, and did about the same after. That particular action got oodles better when a Shilen bull barrel went on it, and even a bit more when the trigger was changed out. It shoots the same first, last and middle.

I have records on this gun since I put it together about a year ago. It got significantly smaller groups with I made one improvement a month or so back (that I haven't revealed yet in these writings). It had always seemed to have something "wrong" with the zero wandering or cold shot or something but I couldn't put my finger on it with so many other variables enlarging the groups. Learning how to do repeatable neck annealings removed a very obvious zero-drops-each-reload issue, and then my undisclosed improvement took the groups down to "touching" shots. This sporter 7mm08 barrel had never done that before. At was then that the cold-shot-error became blatantly obvious and since I couldn't figure it out, after several weeks I went to THR for advice. Thus the scope change, bedding check, etc etc. Still no fix. So now, will change the barrel. That I can do myself (as I did the 6PPC, and this 7mm08 as well) since it is a Savage.

I also have a Mosin Nagant that I've been working on and now have it shooting groups <1" ("touching") at 100 yards. What got me going was that it has NO cold-bore difference, and I wondered why a 74 year-old gun was outperforming a modern hunting rifle....

Orkan
April 16, 2013, 08:50 PM
I also have a Mosin Nagant that I've been working on and now have it shooting groups <1" ("touching") at 100 yards. What got me going was that it has NO cold-bore difference, and I wondered why a 74 year-old gun was outperforming a modern hunting rifle.... I don't understand. Why would you shoot a mosin at 100yds when the target is still well within bayonet range?

BluegrassDan
April 16, 2013, 09:56 PM
Looking forward to seeing your results with the new barrel.

How many inch-pounds do you torque the action screws?

docsleepy
April 16, 2013, 10:28 PM
Good question. "Tight". Probably 75 inch lbs

BluegrassDan
April 16, 2013, 10:40 PM
Are you using an actual torque wrench with accurate settings? By "feel" just isn't accurate enough.

I still stand by my thought that the action screws have uneven torque, and most probably the front action screw being looser than the rear. They should be alternately tightened in 5 lb increments up to around 60 inch pounds to ensure even tension into the bedding. No loctite for action screws, although I do use it on scope mounts.

Looking at your last group of nine or so shots, notice how you've got one shot high, then it settled, then one low, settles again, a couple high around 1 o'clock, settles down, etc.

It could be that your 6mm bench gun is less prone to inaccuracy due to action screw tension thanks to higher quality bedding.

Just my hypothesis.

docsleepy
April 16, 2013, 11:39 PM
Interesting ideas.

1. No, I don't use a torque wrench.
2. Both screws were loctited. They are approximately the same torque.
3. I'm the person who bedded both the 6PPC and the 7mm08. Similar technique.
4. The 6PPC is an old Savage action where the threads on the front threaded hole are damaged. To make it work without having to re-drill and thread to a larger size (with fewer threads) I actually created a stud of the appropriate length, glue it into the damaged threads, and apply a nut from outside the stock. Savages aren't nearly as well regarded as $1000 specialty actions, but then again, I'm not made of money.

In my experience, the alignment and smooth movement of the rifle within the front and rear rests is key to reducing vertical stringing. It is odd to me that virtuall ALL the cold-bore error is vertical. This rifle is a hunting rifle with a narrow forearm. I created a U shaped wooden shim with cutouts for the swivel screw heads, that allows the forearm to move smoothly within the front rest. This was part of what got the groups down to touching. Since the rifle moves within the front rest bags before the first shot is fired (I snug the sides up just until the movement is ever so slightly restricted), I don't think that anything really changes between the 1st shot and followup shots. I could be wrong there, but again, this is my attempt to recreate the exact situation that works with the 6PPC -- which has zero change between first and following shots.

docsleepy
April 16, 2013, 11:54 PM
By sliding properly in the rest, I mean so that the rifle tracks vertically and returns well. The 7mm08 in a cheap plastic stock, can't really do this perfectly. My 6PPC has a weighted stock made by a good (but not great) stockmaker. In the bags, the scope revealed that the aim moved diagonally rather than vertical when the rifle was slid. Indeed, the buttstock was not laterally symmetrical when carefully measured! A bit of duct tape carefully layered and added to make it symmetrical and voile'! The rifle aim point moves perfectly vertical.

There is no way to get the cheap, light, hunting rifle to duplicate all this, but still, it is the FIRST shot that shows the repeatable, always upwards, error.

Attached is a pretty good group while fireforming some Norma 6PPC brass for the reconstructed 6PPC, which got an Evolution trigger....since re-adjusted to 5 ounces. Also a Savage action, much better stock, Shilen stainless match barrel, installed by me, bedded by me, same bag / same rest. 100 yards. 5 shots. If the thing didn't weigh a ton and have such a light trigger and have NO WAY to put on a strap....it would make a nice deer-killing machine. When you're shooting clay pigeons with that gun, you pick which edge of the clay you plan to hit!

Andrew Leigh
April 17, 2013, 03:24 PM
Here's my data from today.
Much hotter in Florida, 85 deg F. GNATS!!!!


As you can see, once again the first shot of high, this case by 1 inch.
The 3rd shot is the low one, I can't explain that.
There are nine shots total and as you can see, the rifle groups pretty well when it is not the 1st shot. The 2nd shot is somewhere in that glob of holes.

VELOCITIES: I dont' have the diffusers, so my chrony is very picky. It malfunctioned on most shots.

1st shot was 2914 fps
4th shot was 2902 fps (in the glob)
8th shot was 2992 (in the glob)
9th shot was 3023 (not sure where it went)

So yes, the first shot is somewhat slower. If that held up, I might could have some rounds with 1 extra grain of powder?

But the shilen barrel is on order now. 9" twist, bull barrel, 22" (short, thick), chrome-moly.

Oh -- one commenter wondered if my rifle "settles" in the rear bag after the first shot. I would consider that a possibilty -- except I do NOT see this with my 6PPC in the exact same front/rear rest.

Hi Docsleepy,

your spread of velocities is much larger than I would consider acceptable. At that speed I would be real unhappy if the spread was greater than +- 15fps.

Do you hand load?

Read this article, it is a great piece of work.

http://www.rifleman.org.uk/Fuller_group_diagnosis.htm

Read from "Diagnosis" and concentrate around Fig 8 and the accompanying text.

Cheers

docsleepy
April 17, 2013, 06:36 PM
Great points.
I don't trust the chrono. Fails too often. Think I should have put up a diffuser

Hand loaded.

That article sure makes it sound like it is the stock or bedding. Some benchrest rifles are GLUED IN so bedding issue disappears.

Maybe I should get a FAT wrench and loosen screws and try better.

drcook
April 17, 2013, 06:54 PM
you all should go over to

http://www.sniperforums.com/forum/sop/31519-sniping-cold-bore-shot.html

military and swat personnel understand the cold bore shot and/or clean bore -vs- fouled bore

docsleepy
April 17, 2013, 09:29 PM
Well, I read that, but they still don't explain the physics of it. For example, one person said his cold bore shot was low. Mine is high. Why? Why one direction and not another?

docsleepy
April 17, 2013, 09:32 PM
Either my barrel is wicked, or there something wrong with my stock or bedding. This just doesn't happen with my six PPC, which is an expensive stock and an expensive barrel. But it also doesn't an happen with my Mosin-Nagant. And you can't call that expensive!

Andrew Leigh
April 18, 2013, 12:59 AM
Hi Docsleepy,

I am a great believer of process control. That is, the abilty to control a process and to willfully take said process out of control and then to be able to return the process back into control.

Reloading is a process. So whats my point. Well simply that we firstly need to ascertain if your reloads are consistent or if your Chrony hates you. Having said which the chances of each first shot being the flyer would be highly unlikely but as stated the spread was rather extreme. But the ammo must be the first check.

In my personal experiecnce faulty / lack of adequate bedding mostly presents as lateral groups and not vertical. Judging by the glob in the middle you can shoot, I am not one you believes in flyers (other than thoses induced by the shooter) you have a couple of "flyer" which probably were not you.

A couple of things to have a quick look at (not trying to teach you to suck eggs here);

-Is your barrel free of the stock? The old dollar note check.
-In a previous post I recommended that you check the firing pin assembly, your symptoms are classic of a broken / weak firing pin giving intermittent strikes. Have you checked your shot cases for varing firing pin strike depth?
- Do you clean your rifle after each range outing and then oil the barrel? If so do you make sure that all the oil is removed from the barrel before your first shot. An oily barrel can lead to 1st shot like yours.
- Do you store your rifle with the firing pin in tension or relaxed? If relaxed it may be that the for the first firing, the spring has rejuvenated a bit and then after the first operation relaxes back to its slightly weakened state.
-How many action screws to you have holding the barreled action in place?

Cheers
Andrew

docsleepy
April 18, 2013, 06:32 AM
Hi Docsleepy,


Reloading is a process. So whats my point. Well simply that we firstly need to ascertain if your reloads are consistent or if your Chrony hates you. Having said which the chances of each first shot being the flyer would be highly unlikely but as stated the spread was rather extreme. But the ammo must be the first check.

In my personal experiecnce faulty / lack of adequate bedding mostly presents as lateral groups and not vertical. Judging by the glob in the middle you can shoot, I am not one you believes in flyers (other than thoses induced by the shooter) you have a couple of "flyer" which probably were not you.

A couple of things to have a quick look at (not trying to teach you to suck eggs here);

-Is your barrel free of the stock? The old dollar note check.
-In a previous post I recommended that you check the firing pin assembly, your symptoms are classic of a broken / weak firing pin giving intermittent strikes. Have you checked your shot cases for varing firing pin strike depth?
- Do you clean your rifle after each range outing and then oil the barrel? If so do you make sure that all the oil is removed from the barrel before your first shot. An oily barrel can lead to 1st shot like yours.
- Do you store your rifle with the firing pin in tension or relaxed? If relaxed it may be that the for the first firing, the spring has rejuvenated a bit and then after the first operation relaxes back to its slightly weakened state.
-How many action screws to you have holding the barreled action in place?

Cheers
Andrew

1. Completely free floated
2. I'll check that firing pin strike depth; hadn't thought of that
3. I'm pretty sure it is stored cocked in the safe.
4. While investigating this, I have tried everything, recently I have not been cleaning it at all.
5. Two action screws, quite tight. Locktite it.

docsleepy
April 18, 2013, 06:33 AM
Maybe I should've bought a new stock, instead of the barrel. My six PPC is in a stock made by Rayhill.

Hummer70
April 18, 2013, 07:48 AM
FWIW looking at the striker indent on a fired primer is not much help. It should however protrude .040"-.060" through the bolt face.

The striker spring taking a "set" (get shorter from being compressed for years) is another possibility and unless you have the equipment to determine striker energy (I do) then you don't really know what you have. Properly made springs should never take a "set".

In the testing business what we did with all compression springs was to remove them from new weapons and measure their free length and record it. Then every 1200 rounds the springs would be removed and measured again to see if they became shorter.

Wolff Springs generally make three grades of springs, "factory replacement", then a heavier medium and an even heavier spring. I always upgrade to a medium spring at a minimum. The industry standard was relaxed a number of years back from having a Min .020" striker indent (on copper pellet) and only "recommending" .016" indent.

Higher energy is recommended to assure ignition uniformity. Lets see if I can explain it. the industry pretty well figured out that .009" indent or less was a all no fire. Where .012" or deeper was a all fire. Frankford Arsenal found out in testing years ago that as the striker energy drops off vertical dispersion increased even though 100% ignition was being achieved.

I have a M1911 Swiss rifle that gives .022" indent. I had a La Corona 98 Mauser that gave .024" indent and I can't get a US made rifle to give me over .020 with factory spring.One is near on 80 years old and the other is 50 years old.

Another thing that has an effect is the amount of off center striker hits. Frankford studies also proved that up to a .020" offset there was no effect on ignition reliability but after .020" the misfire rate goes up. Which begs the question why are the gov't weapon specs allowing 1/2 diameter offset (of striker nose) to be fielded.

Try the following:

1. leave the copper in the bore but remove the propellant fouling quickly after firing.
2. Use synthetic grease on patch and make multiple passes until the patches come out same color as they went it. I use Grease Auto and Artillery GAA or Grease Aircraft Wide Temp Range WTR which are NATO spec greases.
3. The Swiss Army has used grease to clean bores over a hundred years now and I have never heard of a surplus Swiss rifle with a bad bore as received.

I normally run about 20 greased patches in bore ten passes. This will remove about 99.5% of the carbon (which is the enemy here). You want a tight fit so when the patch goes in bore it presses snugly on the walls of the barrel. I generally use a .27cal black nylon brush of a smaller caliber and wrap a 30 cal patch on that to give me a snug fit. When finished I leave grease in the bore.

A tight fitting patch will just leave a non visible trace of grease you cannot detect by visual examination. If you can see the grease left in bore your patch is not tight enough.


I believe your first shot will not be nearly as far out of the group.

Most importantly after your last shot remove quickly and get a greased patch downbore to remove the carbon. Carbon left to cool becomes hard and acts as an abrasive.

Nevmavrick
April 18, 2013, 08:20 AM
Another WAG. I appears to me hat the whole rifle is being "bedded" on the first shot. Comparing the hunter with the BR-gun is unfair to both. Also the M-N is different just by the fact it's different. I think it best to treat the gun as an individual.
Barrels have a tendency to "squirm" in a more-or-less circle as they are shot, from pressure and heat. Most of the time this "squirming" is in a figure 8. With a light (the lighter, the more obvious) barrel, you try to nullify, more or less this tendency.
Also, each powder, and charge, not to mention bullet, modify this tendency. That is why the first shot COULD be in any direction. By changing the load, the direction MAY be changed. My thought on THIS matter is that if you change powders, you'll find the direction the first shot goes will differ.
I'm not real sure what the "guide" does in this matter, but I'd try it without. It may take a slightly different technique to BR the gun, but that's OK, too.
I agree that it may be a natural thing to have happen, but it's too radical to allow on a hunting rifle. The difference HAS to be reduced!
The light hunting barrel is quite often in need of upward pressure, which you've reduced by cutting some of the stock away (not a bad thing...yet) You might put more pressure UP by putting a business-card shim under the barrel at the tip of the forearm. Then, 2 or 3 more as the experiment continues. If it doesn't work, they can come out.
MY opinion, FWIW, is change the powder first.
Have fun,
Gene

docsleepy
April 18, 2013, 05:18 PM
Higher energy is recommended to assure ignition uniformity. Lets see if I can explain it. the industry pretty well figured out that .009" indent or less was a all no fire. Where .012" or deeper was a all fire. Frankford Arsenal found out in testing years ago that as the striker energy drops off vertical dispersion increased even though 100% ignition was being achieved.

I have a M1911 Swiss rifle that gives .022" indent. I had a La Corona 98 Mauser that gave .024" indent and I can't get a US made rifle to give me over .020 with factory spring.One is near on 80 years old and the other is 50 years old.

Another thing that has an effect is the amount of off center striker hits. Frankford studies also proved that up to a .020" offset there was no effect on ignition reliability but after .020" the misfire rate goes up. Which begs the question why are the gov't weapon specs allowing 1/2 diameter offset (of striker nose) to be fielded.

Try the following:

1. leave the copper in the bore but remove the propellant fouling quickly after firing.
2. Use synthetic grease on patch and make multiple passes until the patches come out same color as they went it. I use Grease Auto and Artillery GAA or Grease Aircraft Wide Temp Range WTR which are NATO spec greases.
3. The Swiss Army has used grease to clean bores over a hundred years now and I have never heard of a surplus Swiss rifle with a bad bore as received.

I normally run about 20 greased patches in bore ten passes. This will remove about 99.5% of the carbon (which is the enemy here). You want a tight fit so when the patch goes in bore it presses snugly on the walls of the barrel. I generally use a .27cal black nylon brush of a smaller caliber and wrap a 30 cal patch on that to give me a snug fit. When finished I leave grease in the bore.

A tight fitting patch will just leave a non visible trace of grease you cannot detect by visual examination. If you can see the grease left in bore your patch is not tight enough.


I believe your first shot will not be nearly as far out of the group.

Most importantly after your last shot remove quickly and get a greased patch downbore to remove the carbon. Carbon left to cool becomes hard and acts as an abrasive.


1. By using a pin with a piece of skotch tape as a transfer device, and trying different settings of the tape, I was able to get a measurement of the degree of primer pit This was not easy. I estimate AT LEAST .016 and likely .018"

2. The firing pin pits are not exactly dead center. The fired primer is .143" wide, and the edge of the pit appears to be as much as .010" closer to one edge than another. However, that's pretty close to centered.

3. The grease idea is fasincating, especially since my (possibly flawed) measurements indicate that the first shot might be considerably slowed.

4. I don't have any "synthetic grease" but I'll give this a try. This is interesting. It seemed very much to me like something "left behind" was doing it. I have some gun grease and some disk brake grease. I'll look into this.

THANKS FOR THE IDEAS!!!

docsleepy
April 18, 2013, 09:36 PM
OK, we may be making progress!

I tried Hummer70's idea. The only "grease" I had readily available was some "gun grease" called "PRO-GOLD". So I got the biggest patches that I could get through the bore/bore guide and patched about 6 patches with some grease on them, each one at least twice. The gun had not been cleaned after the previous session. The patches started dirty and became progressively cleaner, to close to clean.

Shooting was same as before, front rest, wood cradle for the skinny forearm, rear bag, firm hold, 100 yards, 16x scope. It was a busy day, so I only had about 15 minutes of sunlight left (range closes). Got three shots off. 1st and 2nd were amazingly close, and the third, while off a bit to the right, has almost the same elevation.

Of course, one can only do ONE "cold bore" test at a time, so this is only 1 test. Will need to try this several more times, but at least the shots were similar.

Andrew Leigh
April 19, 2013, 12:18 AM
Great news.

So if I understand this process correctly. The barrel is left with the copper fouling and only the carbon fouling is removed. Would this be an indication of a failing barrel which needs plating to perform as normal?

@Hummer70. Surely this would not be considered normal practice on any barrel?

docsleepy
April 19, 2013, 12:29 AM
Good question. In the beginning, it was a factory fresh (cheap) $85 Savage sporter (thin) 7mm08 barrel, 22 inches long. It did get a special treatment a month ago which greatly improved its consistency and made the previously suspicioned cold shot problem become very obvious. (you can guess if you read the thread, "What you can do with a Mosin") I would guess that it has had around 500 shots, mostly in the middle range of power.

3212
April 19, 2013, 10:22 AM
I have had this same problem with a 1958 Winchester model 70 in .243 caliber.So,I shoot 3 shots before the final sight in.Then I do not clean it before the hunt.I have taken more than 40 deer with it using this sight in method.No modifications to the rifle.After the hunt it gets a thorough cleaning.My longest kill shot was 270 yards.

docsleepy
April 19, 2013, 01:48 PM
3212: My problem was that even when left uncleaned, first shot would not be as predictable as others.

3212
April 19, 2013, 07:44 PM
I understand the desire to have every shot placed precisely.It may be that my first shot at a deer is 2 inches from my point of aim.If I can see the deers chest it doesn't matter.I've usually got a 12 inch diameter target,maybe less if the deer is at an angle.I won't shoot at a tail.Now if you're in a shooting contest go for the precision.

docsleepy
April 19, 2013, 08:09 PM
Deer can be at great distances. Missed a 275 yard shot. 2 inch at 100 implies an angular error that makes 5" at 275 according to jbmbalistics. No one is a perfect shot. Add a small additional error and pretty soon you have missed or only wounded the deer.

3212
April 19, 2013, 09:49 PM
On my 270 yard shot,I held high on the shoulder and the bullet entered the lower chest.So several inches higher would still hit the vitals.At that distance the bullet was beyond the midpoint of its trajectory.At the midpoint it may have been a problem.But I shot a buck at 180 yards facing me at 3/4 profile.All the others were from about 150 yards to 20 yards.The .243 has a pretty flat trajectory if you look at the charts.A cartridge with a different trajectory might cause problems. I never hold above the deer(off the brown).

docsleepy
April 20, 2013, 06:28 AM
Great advice! Certainly novice at hunting. Didn't even have a firearm until our current president. So lots to learn!

3212
April 20, 2013, 08:16 AM
I think you will be fine with that rifle or any other rifle when you become familiar with it.Before the .243 I hunted with a scoped Marlin 30-30 for 25 years.I missed a couple and then settled down and took 16 with it.

docsleepy
April 20, 2013, 06:07 PM
My next chance to try some more cold bore data collection will be either Tuesday or Saturday. Will see if this grease trick holds up. If it does, I may have a spare match barrel laying around for nothing. Maybe I'll make yet another rifle!

gamestalker
April 21, 2013, 06:46 PM
There are a number of possible causes, but my experience is simple, that a cold bore shot is always off the center group of a warm barrel. You'll probably, and likely, never know what is the culprit, it's just the nature of long guns in general. I have a number of high powers, and all of them shoot consistently high, low, or what ever with the first cold shot. Now if you start having trouble with groups, then you have something that needs tending to.

I have a 7 mag that shoots extremely high on the first cold shot 3"+ depending on the load I'm using, always has, and probably always will, but after that first cold one, it will shoot 1/2" all days long at 200 yds. if I'm doing my part that is.
GS

docsleepy
April 22, 2013, 07:14 AM
Well, you may be right. But I have a couple of rifles don't act that way. I have an AR 15 where the first shot groups normally and an accurate Mosin whose first shot also groups with all the rest. My benchrest 6ppc first shot appears to be insignificantly off from a hunters perspective. But this 7mm08 was 2" off. Last test after grease cleaning was encouraging. Will report another test hopefully tomorrow.

docsleepy
April 23, 2013, 06:27 PM
Here is my 2nd test of the cold-bore shots using the "grease" technique. I'm not exactly following the directions, but I'm close. Ran greased patch up the bore multiple times, until no more carbon picked up, finished with a dry patch.

Was unable to measure any velocities today. (I did however, add a homemade diffuser after these shots, made out of several sheets of white paper, and was able to get some velocities from a Mosin Nagant that showed the first shot was slower than the rest, uncleaned)

THe first shot is still high, but not nearly as high as I had been experiencing before, so it seems to me that this IS helping. The first shot of this cold bore test is less than 1.5" higher than the middle of the remaining shots -- this is probably do-able as a hunting rifle. First shot anywhwere from 0 to 1.5" higher than the typical group, gives tolerable accuracy to 200+ yards.

Shilen has notified me that they are about to send my new match barrel to the chambering dept -- so maybe I'll have a new barrel soon.

Orkan
April 23, 2013, 06:41 PM
If that helped... then I'd be inclined to believe that it's your barrel. ... and a rebarrel will completely resolve the issue.

Thanks for your diligence in updating this Doc. Can't wait to see the resolution.

ironworkerwill
April 24, 2013, 11:25 AM
I am stoked! I can't wait to see the holes that shilen makes for you. I've been watching this thread like a hawk. The only way it would be any more interesting for me is that if you were getting a brux screwed on.

MrBorland
April 24, 2013, 12:06 PM
Interesting thread. As I started reading the thread, my initial thought was that the receiver face needs to be trued - once it warms up, it pushes on the barrel unevenly, so the remaining shots go to a different place. Orkan touched on this in his earlier post (http://www.thehighroad.org/showpost.php?p=8875883&postcount=48). I'd be interested to see if your new barrel fixes the problem.

Highland Ranger
April 24, 2013, 03:17 PM
This says breaking wrist up . . . . .

http://www.thehighroad.org/attachment.php?attachmentid=183213&stc=1&d=1366831043

(oops - not a handgun - I'll leave it here anyway . . . . )

WardenWolf
April 25, 2013, 02:55 AM
"There's no meat in the freezer and I know why. . . Because I shot high, because I shot high, because I shot high. . ."

Sorry, I couldn't resist. I'm guessing your bore is just very fouling and / or temperature sensitive. It really shouldn't be that bad, though, unless your barrel is very thin and lacks rigidity. It also could have to do with how it interacts with the stock. Hopefully whatever you try fixes it.

docsleepy
April 27, 2013, 10:12 AM
OK, gang, it is looking like HUMMER70 absolutely NAILED it. Here are today's cold-bore test results, which show a striking improvement over my results before adopting his "greased patch" technique.

Shot #2 is in the black to the left. Pen doesn't show up there well. Shot #4 is inexplicably "off". The rest are very well grouped.

Annealed, many-times-used, full-length sized (ran in and out of sizer 3 times), then trimmed, beveled, smoothed in steel wool, neck sized, 41.2 grains Varget (my summer-time-load, as the 42 grain was over-pressure recently), 120 grain Sierra spire-point hunting round, seated to just about 10 thou off the lands from previous tests. Seater is more consistent if you run it up into the seater twice.

HERES THE KEY: (adapted from HUMMER70 suggestions):
Pro-Gold rifle lube applied sparingly to patch, run from breech to muzzle using boreguide, about 5 such patches, each run AT LEAST twice, pretty clean by the time I was done, this time I finished with a greased patch, instead of finishing with a non-greased patch. The idea was to leave a film of grease in the bore.

Benchrest technique, u-shape shim wooden contraption around skinny forend of cheap cheap plastic stock, running in Rock BR front rest, rear leather bag, smoothly running, very firm grip (pulling into shoulder pocket), 16X scope, held dead center on target with no discernible shake (rifle intentionally zeroed a bit high at 100 yards). Chrony this time with diffuser worked much better.

Shot Velocity POI
1 2902 3.5"up, 1"R
2 2848 3" up 1/2"R
3 2896 3.25"up, 1.25"R
4 2838 2.25"up, 0.75"R (no idea why)
5 2840 3" up 5/8" R


Really looks like Hummer70's idea is the key.

Shilen barrel is still headed my way!

docsleepy
April 27, 2013, 10:15 AM
If anyone is interested, midway carries this grease. It was the closest thing I had to what HUMMER70 recommended:

http://www.midwayusa.com/product/470044/pro-shot-pro-gold-gun-grease-lubricant-10cc-syringe

Andrew Leigh
April 27, 2013, 01:57 PM
HUMMER70, help me out here.

I don't understand the science behind this. It obviously works but are we not treating the symptom and not the cause?

I leave my barrels oiled, the first thing I do on the range is to run patches through them to dry. If I don't dry the bore I get a flyer, exactly the opposite.

@ Docsleepy. Why do you run you case through the FL die three times? You are work hardening the brass, is that what you want?

I sorted your results according to velocity.

Shot No. Speed Vertical
4 2838 2.25"
5 2840 3.00"
2 2848 3.00"
3 2896 3.25"
1 2902 3.50"

Average speed 2865 fps
Std deviation +-32 fps

- Your vertical displacement is roughly consisent with your velocities.
- Your standard deviation is about twice what what it should be to be considered OK, not good. Forgetting for a moment your initial problem I believe you could reduce your vertical displacement significantly if you could get your speeds more consistent.
- Do you individually weigh each powder charge or do you rely on a powder dispenser?

Orkan
April 27, 2013, 02:36 PM
It obviously works but are we not treating the symptom and not the cause? This is my opinion exactly.

Lots of methods to "work around" problems. I'm a fan of solving them outright. I have enough to keep track of. I certainly don't want to keep track of a regimen that a certain rifle likes in order to produce accurate results.

docsleepy
April 27, 2013, 02:37 PM
I've had problems with annealing. I don't have a fancy machine to do it, I do it by hand. So I intentionally work harden the necks a bit to try to hopefully bring them to a happy medium. I doubt that the work hardening they get from hand hand pressing is anything close to what happens when they get hit by 50,000 PSI And stretched to meet the neck walls of the chamber. But I could be wrong!

If you have any brilliant ideas to decrease my velocity dispersion I'd be happy to hear them! I use a Lee perfect powder thrower, and typically am within .1 grains. But this is Varget, and it doesn't meter perfectly. I have a charge master, but it is somewhat slower, and I haven't seen much of a difference in the past.

Shot number four still doesn't make any sense. Only 2 ft./s can't make that much difference. I'm guessing it has something to do with the particular hold on the rifle for that shot.

docsleepy
April 27, 2013, 02:39 PM
Before I annealed the zero would consistently change from week to week to week as the neck hardness changed. Annealing brought a significant improvement. Remember this is an $85 barrel.

Andrew Leigh
April 28, 2013, 03:23 AM
I've had problems with annealing. I don't have a fancy machine to do it, I do it by hand. So I intentionally work harden the necks a bit to try to hopefully bring them to a happy medium. I doubt that the work hardening they get from hand hand pressing is anything close to what happens when they get hit by 50,000 PSI And stretched to meet the neck walls of the chamber. But I could be wrong!

If you have any brilliant ideas to decrease my velocity dispersion I'd be happy to hear them! I use a Lee perfect powder thrower, and typically am within .1 grains. But this is Varget, and it doesn't meter perfectly. I have a charge master, but it is somewhat slower, and I haven't seen much of a difference in the past.

Shot number four still doesn't make any sense. Only 2 ft./s can't make that much difference. I'm guessing it has something to do with the particular hold on the rifle for that shot.

Hi Docsleepy,

moving away from the first shot flying.

OK I understand what you are trying to achieve on the case hardening, I do think that you will battle to control the consistency and therefore neck tensions could differ significantly. This will impact on accuracy and bullet speeds. Is there any way you can duplicate your shooting exercise with brand new cases to remove most the variability of neck tension?

Throwing to 0.1gr is fine and you can't see the difference at 100yds. Checked the Sierra software and you are close with your load vs. speed. Sierra also shows that you have an effective zero on the rifle at 260 yards to get 3" high at 100yds.

The shot with 2fps difference in vertical the could be the shooter, I have experienced similar.

Have you considered a different bullet weight? Some bullets weight simply don't agree with the rifle. My 30-06 shoots a 165 better than a 180 although I still load 180's for hunting.

When load developing I get a couple of patterns that can present, one is vertcal dispersion, the other is lateral dispersion and as I get closer to the perfect load the pattern become more random and triangular (use three shots for development). Is there a chance that your load may not be fully developed?

You only have a lateral dispersion of 0.75" which is great. So if you barrel was shot out how come it only affects performance in the vertical plane?

So theoretically the factors that give varying vertical displacement are;
- Erratic firing pin strike (weak / broken spring) you have discounted this already.
- Front rest being too hard, you have discounted this already.
- Variable loads, discounted at .1gr difference.

That leaves possibly
- Bullet weight not perfectly suitable
- Varying neck tension
- Breathing control
- Load not on an accuracy node.

Unfortunately I have no brilliant ideas but this is what I would do. Either nothing and wait for the new barrel and hope that sorts the matter out or;
- Get some brand new brass
- Do the Dan Newberry's OCW development routine and ensure that your load with new brass is correct and on an accuracy node.
- Once the load is established then conduct your cold firing routine with and without grease.

Good luck in your pursuits.

docsleepy
April 28, 2013, 02:59 PM
Hi Docsleepy,

moving away from the first shot flying.

OK I understand what you are trying to achieve on the case hardening, I do think that you will battle to control the consistency and therefore neck tensions could differ significantly. This will impact on accuracy and bullet speeds. Is there any way you can duplicate your shooting exercise with brand new cases to remove most the variability of neck tension?


Have you considered a different bullet weight? Some bullets weight simply don't agree with the rifle. My 30-06 shoots a 165 better than a 180 although I still load 180's for hunting.

When load developing I get a couple of patterns that can present, one is vertcal dispersion, the other is lateral dispersion and as I get closer to the perfect load the pattern become more random and triangular (use three shots for development). Is there a chance that your load may not be fully developed?

You only have a lateral dispersion of 0.75" which is great. So if you barrel was shot out how come it only affects performance in the vertical plane?

So theoretically the factors that give varying vertical displacement are;
- Erratic firing pin strike (weak / broken spring) you have discounted this already.
- Front rest being too hard, you have discounted this already.
- Variable loads, discounted at .1gr difference.

That leaves possibly
- Bullet weight not perfectly suitable
- Varying neck tension
- Breathing control
- Load not on an accuracy node.

Unfortunately I have no brilliant ideas but this is what I would do. Either nothing and wait for the new barrel and hope that sorts the matter out or;
- Get some brand new brass
- Do the Dan Newberry's OCW development routine and ensure that your load with new brass is correct and on an accuracy node.
- Once the load is established then conduct your cold firing routine with and without grease.

Good luck in your pursuits.

1. At present, all things ammunition are in short supply in the U.S. New match Hornady .308 cases aren't in stock where I've checked (I neck down to 7mm to obtain a tighter fit). I have some one-fired Remingtons that I might press 5-10 into service to give your theory a test.
2. I've done the ladder thing to the tune of several hundred bullets in the past on some rifles without ever reaching a REPEATABLE effect. Chance favors drawing incorrect conclusions I fear. Hence I just picked a bullet weight and haven't really investigated powder. Might be worth some effort.
3. I'm just very impressed that this $85 barrel is now shooting in the MOA range! even the first shot! (in 2 of three cold-bore tests so far).
4. I have seen velocity numbers before that are just amazingly consistent. So far, I haven't been able to do that....maybe I should try a benchrest or magnum primer, dunno. I believe I have some magnum LR primers, but beyond that....nothing is available in the U.S.

BullfrogKen
April 29, 2013, 12:18 AM
I think the culprit here is your reloading technique.

You're totally over-working your brass. Being a new gun owner, I imagine you're even a newer handloader.

I don't think it's the rifle so much as your handloading process.

Are you measuring your catridge OAL? Are they consistent? There's something quite wrong here if you're getting velocity spreads that wide.

docsleepy
April 29, 2013, 11:12 AM
I think the culprit here is your reloading technique.

You're totally over-working your brass. Being a new gun owner, I imagine you're even a newer handloader.

I don't think it's the rifle so much as your handloading process.

Are you measuring your catridge OAL? Are they consistent? There's something quite wrong here if you're getting velocity spreads that wide.

One. Well maybe you're right that I'm overworking the brass. I can certainly try switching to the more normal technique after annealing. I'm pretty sure that I've tried it also in the past, but no harm in trying it again.

Two. I'm not sure why I am a new reloader? I reload seven calibers, and have probably done five or 6000 reloads by now. I'm getting groups under an inch with my reloads for a Mosin-Nagant; 6ppc groups using a homemade rifle down into the 3's

Three. I'm not sure why I am a new firearms owner? It is true that I did not have any firearms until after the election of 2008. However at this point I fill multiple safes. This particular gun, Was a sporter .223 that i rebarreled (just a thou or so over the minimum of the go-gage) and switched out the bolt head.


But I was completely perplexed by this high first shot problem and so came here to learn more. I'll certainly give your ideas a try!

docsleepy
April 29, 2013, 11:15 AM
Oh, and on the cartridge overall length: I have tried to keep these within a couple thousandths . I am a few thousandths off of jammed into the lands. Several different experiments suggested this was the optimum point.

The next chance I get, I'll reload some new brass, and I might learn something very important! Already, the grease tip seems to have made a huge improvement!

docsleepy
April 29, 2013, 11:30 AM
http://www.snipercentral.com/matchammo.htm

Since I don't know a whole lot about velocities, I looked at this article on the measured velocity and extreme spread of commercial match ammunition. I'm certainly not in the best of this group, but I appeared to be even with some of them. There seems to be an impact of the rifle chamber, and I'm dealing with a very very cheap barrel. Unfortunately, my brass has differing numbers of usages, and probably ranges from 5 to 15.

Andrew Leigh
April 29, 2013, 02:42 PM
Hi Docsleepy,

the ladder method and the OCW method are quiet different but both effective.

To effectly use the ladder method one have a target out at about 600m for results to truely show as the method relies on vertical displacement only. The OCW method does not rely of vertical displacement but rather group pattern and size, triangulating the group and the POI.

It normally takes me around 30 rounds to fully develope a load from scratch. I have placed the method into spreadsheet format. If you are interested PM me you mail address and I will forward it.

BullfrogKen
April 29, 2013, 11:45 PM
doc, buying a whole bunch of guns in a hurry does not buy you the experience that comes along with them.


Having velocity spreads that wide would be totally unacceptable for my handloads. Before I did any other thing I'd find out what my loads were so inconsistent.

docsleepy
April 30, 2013, 09:24 AM
Good advice!

docsleepy
April 30, 2013, 06:07 PM
OK. In the quest of reducing velocity dispersion. (I'll get to the OCW effort a bit later)

No way to get "new" cases, so for Group 1, I gathered 5 "once fired" .308's Remington that I had on hand for another gun. FL size, trim, bevel, neck size, prime, 41.2 gr Varget from Chargemaster, seat bullet. Note I generally always neck down .308's for 7mm08 so I end up with a tighter fit in the neck region in my sporter barrel.

Group 2: 5 previously fired cases: necksize, no trim, prime, 41.2 gr Varget from Chargemaster, seat bullet (these felt much less neck tension)

Group 3: 5 previously fired cases: FL size, prime, trim, bevel, no neck size, 41.2 gr Varget from Chargemaster, seat bullet.

Gave up on heading 29 miles to the range this late (spent most of day working on an engine), may be able to anneal some cases tonight, create another test group, head to range tomorrow. If I do, I will run them into the FL sizer only ONCE.


Discoveries so far:
1. My Lee bullet seater was seating much less precisely than I had remembered. These are light-for-caliber 120 grain Sierra spire points. The cases group in group three (tighter neck tension) tended to have too-long COAL by .005 or more ; the cases from group two (much looser neck by my "feel" of the press) tended to have too-short COAL (by roughly .004) ....this was unexpected. And, since I'm near "lands" -- this might be very significant. [In 6PPC, my Lee did just about as good as a Wilson! so this is a useful discovery for me. Perhaps I need a better or custom seater......] I readjusted the worst outliers....by COAL.

2. I have a simple Hornady comparator set, may check that on them, if so, perhaps adjust for similar comparator readings?

3. Note that I switched to the Chargemaster to avoid issues of powder variabilities.

BullfrogKen
April 30, 2013, 06:15 PM
What do you mean, "No way to get "new" cases"?

Midway has some available right now -


http://www.midwayusa.com/product/1311133737/norma-reloading-brass-7mm-08-remington


That stuff is still factory produced. Buy some and I'll be shocked if using it doesn't reduce that huge velocity spread.

docsleepy
April 30, 2013, 10:04 PM
What do you mean, "No way to get "new" cases"?

Midway has some available right now -

http://www.midwayusa.com/product/1311133737/norma-reloading-brass-7mm-08-remington

That stuff is still factory produced. Buy some and I'll be shocked if using it doesn't reduce that huge velocity spread.

BullfrogKen:
Yes, I saw that, this afternoon, put it in my "cart" even, and then took it back out. [You are right, 7mm08 is available (at $1/case) ; I should have said that what I PREFER isn't...]
I prefer Hornady match 308 to neck down, and besides, I simply can't be dependent on "new" brass for every shot!! (Lapua .308 is also available....at a price) I worked with 50 ppc cases for months and months; I've read that many competitors use the same brass for the entire life of one competition barrel; hopefully this can be done with this rifle also with some form of reloading....
....I don't have money to burn and I settled on getting some more bullets for 7mm and 6.8SPC, until I have the results of this current test to see if indeed less-worn brass is better....

I still don't get why these are "huge velocity spreads" when they are similar to some "match" ammunition that I cited in the article published online?

If indeed I am "overworking" the brass, then wouldn't annealing the neck and simply full-length sizing it once be adequate to address your concerns?

And besides, does this have ANYTHING to do with the "first shot" problem? How would it be that my brass knew which one was destined to be FIRST to be shot, during reloading? I think it would be great if I could improve my process, but the major improvement (to date) has been to grease-patch that barrel.

Why don't you give us a rundown on how YOU handload and perhaps I might learn something? That would probably be VERY helpful!

Andrew Leigh
May 1, 2013, 01:12 AM
It may or may not have something to do the the first shot flying but first we need to get the velocity spread down. This is a variable that we know that is higher than it should be and must therefore be taken out of the equation before proceding. There is a direct correlation between velocity spread and accuracy, in my loading experince that is. I like mine below +-15fps and get real warm and fuzzy when they are below +-10fps.

murf
May 1, 2013, 01:26 AM
so, how does factory ammo work in that gun?

shoot a five shot group of that factory ammo over a chrony. easier to discuss your quest if you have a baseline for comparison.

murf

BluegrassDan
May 1, 2013, 07:22 AM
I think you're over complicating this. There should be no need to overwork the brass so much. I don't spend nearly that much time on brass prep and my Kimber groups sub-MOA.

The grease thing should not be necessary.

Inconsistant velocities could be a culprit. I still think you need to check the torque with a real torque wrench.

docsleepy
May 1, 2013, 05:03 PM
BluegrassDan -- I just had to chuckle reading your post! Yep, I think we are over complicating it....but then again, if **I** had a KIMBER, then I probably wouldnt be having the problem!!!


I think everyone is going to be much happier with the velocity data that I collected today.

Today was a completely overcast day here. I am just not an expert at getting my chrony to work, except on overcast days: it worked perfectly today. Where I shoot is bordered by trees and hills, and on sunny days (like the day I collected the past data that drove everyone crazy), it is just really difficult to get that chronograph to work well. A diffuser helps, but still some shots it just won't register. I have to wonder about its accuracy on those days.

ANYWAY: I made up different batches of rounds as above; the 4th group was my usual technique, but only ONE FL resize. The usual technique is: Deprime, Anneal neck, dry, lube, FL resize (1 or 3), trim, bevel, smooth, necksize/prime, Lee powder thrower, bullet seat, wipe off lube.

Each group differs in some way, as noted below.

docsleepy
May 1, 2013, 05:11 PM
The first set to be shot was Group 4: my much-used Hornady brass, annealed, FL sized (only once this time), trim, bevel, smooth, necksize, Chargemaster 41.2 grains Varget, seat 120gr Sierra SP, trying to keep Hornady .28 comparator measurement between 2.272-2.276. This took some doing.

Average velocity is 2881, SD is 27.1 The first shot is a bit high, and I dunno exactly what is happening with that last shot.

Prior to doing all this, I re-measured the COAL to the lands, Hornady device. Couldn't find my test shell, had to make another one....took a while. Lands are at a comparator length of 2.273. COAL of 2.769-2.772.

Loaded round neck dia is .312. From a fired shell necked up and down until it would JUST BARELY go into the throat, my rifle's throat is just over .316, meaning I have .002 on each side.

docsleepy
May 1, 2013, 05:16 PM
The second group shot is Group 1 -- "once fired" RP brass .308, "new" to me, not annealed, FL sized x 1, necksized x 1, chargemaster 41.2 grains, bullet seated to similar specs as above.

Average 2898, SD 10.1 ( much better). Note the zero is moving.

docsleepy
May 1, 2013, 05:20 PM
The third group shot is supposed to be old cases, annealed, FL size, skip the neck size (Group 3). Unfortunately, the first shot (#11) I picked up a case that belonged to Group 2 (neck size only).

For the shots #12-#16 in Group 3 (skip the neck size) the average velocity is 2918, SD 8.43.

Also note, that prior to this group, I noticed that the chrony had been turned approximately 5 degrees (which would give slightly erroneously low velocities) and I fixed that prior to this group.

I shot a total of 20 shots over about 45 minutes, and the barrel gained some warmth. The zero is now lower and leftward of where it started.

docsleepy
May 1, 2013, 05:25 PM
The final group is old cases, annealed and neck sized only. Shot #11 in the previous photo should belong to this group, so I have pencilled in where it would have been on this photo. The average velocity is 2901, and the SD is 6.6 fps.

These cases have obviously lower neck tension when you seat the bullet. The zero is lower.

One of the rounds is pretty short -- comparator 2.263, and it groups lower than the others.


I'm sure you figured this out by now, but each shot is numbered, and the comparator length (Hornady .28 comparator, zeroed with the comparator between the jaws) is listed first, and the velocity is listed second.


OK guys, what do we learn from these? Despite the grease, that first shot (#1 in previous photo) is still a tiny bit high....although much much better than the 2-3" I had been seeing when I first started this thread.

docsleepy
May 1, 2013, 10:37 PM
Murf: Don't actually know how store bought works in this gun. Haven't ever bought any, since they often want $30+ for twenty rounds. With the good velocity data achieved today maybe ill be ok with just my handloads


Andrew Leigh sent me very helpful stuff to do an ocw analysis. My next chance for that wont come until the weekend or later. But good idea. I still don't have a FAT so all I can say is those screws were TIGHT.

Andrew Leigh
May 2, 2013, 01:06 AM
Great stuff Doc,

I feel that you have made real progress here. Those last std d's are looking awesome. Methinks that neck tension was a major culprit which you now have a better handle on.

I think that when you are through with the OCW that you will be able to see if indeed you load was on an "accuracy node" which I don't think it is. Please fire 3 fouling shots before starting with the OCW. From a load development perspective let's not allow the first one or two flyers to influence that. Let's first make sure the load is correct and then sort out the flyer.

I think you mentioned elsewhere in the thread that you were able to do sub MOA groups on other rifles. If it were not for that fact I would mention breathing control. I have e-mailed you another document to read, go down an have a look at figure 8, you may have a deja vu moment. Or as my friend say a deja moo moment ...... where have I seen this BS before :D.

docsleepy
May 5, 2013, 10:35 PM
OK, I'm going to attempt the OCW process [strongly urged by Andrew Leigh] tomorrow, weather permitting.

It should be sunny, and that probably means my chrony will give screwy results.

I will shorten the COAL by .010 to back off the lands a tiny bit, and attempt to use exactly the same reload techniques and quality that I used in the most recent efforts. I'll attempt about 6 or so 3-shot groups differing by 0.4 grains, using a Chargemaster to create the loadings. Three foulers at the beginning, grease patches at the beginning.

Weather is supposed to be cold here, in the high 50's. I'll attempt to let the gun cool fairly well between groups.

Andrew Leigh
May 6, 2013, 05:13 AM
Hey Doc,

wish you well with your loads. Just a thought, the three foulers will take care of the shooting high syndrome so I would not use the grease for now. I still think it is treating the symptom and not the cause. I do not know of anyone who uses such a practice when developing loads.

Do you have a beam scale and powder trickler? Personally my chargemaster is not accurate enough. If you have the beam scale I think for this exercise that you will get better results.

Don't forget to the order in which to shoot. Load 1, Shot 1, Target 1 and then Load 2, Shot 1, Target 2 thaen Load 3, Shot 1, Target 3 etc. This is important 'cause as you barrel warms slowly the POI shifts, at least this way it shifts the same for the three different sequences of shots so you should get great repeatability. The POI is not crucial, the group size and pattern is.

Good luck, can't wait for the results.

docsleepy
May 6, 2013, 06:10 AM
Well, too late, all the charges are already made on the charge master. Find has the original algorithm and works reasonably well.

I'll skip the grease if you think that best. I understood the round robin technique

Andrew Leigh
May 6, 2013, 07:47 AM
Yip skip the grease for now.

docsleepy
May 6, 2013, 05:32 PM
Here are the results of the OCW tests:

Temp in the 60's and 70's, hence able to go up to 42.2 grains Varget, 120 grain Sierra SP. Seated approx .010 deeper, thus approx .010 off the lands, Hornady comparator roughly +/- .002 variation. 0.4 grain steps. I did run a modest number of lightly greased patches, and then shot 3 foulers -- but the 2nd and 3rd were not on the same line, so I shot one or two more until it seemed really consistent. It was a bright sunny day, and I had several sheets of paper attempting to create a diffuser for the chrony....which promptly caused the rods and diffuser-paper to fall over....so I gave up on the chrony.

I had two more Hornady Match Brass show signs of separation, so I had to use some RP brass (same brass that were used in the last test above). Shots fired with this brass are outlined in blue sharpie.

My educated estimation of the geometric center of each group is marked with a red circle. The third photo shows where the centers moved with each set of powder.

The shots were done "round robin" (as per the OCW instructions), NOT all three at one powder level at a time. 16X scope, 100 yards, 7mm08 caliber.

docsleepy
May 6, 2013, 05:35 PM
Here is the compiled set of "estimated geometric centers"

So which is the best powder charge to use??? What do I do with the anomalous results (strangely low) at 41.6 grains??

docsleepy
May 6, 2013, 09:36 PM
Midway today has Hornady .308 match cases available.....restocking my supply!

Andrew Leigh
May 7, 2013, 12:53 AM
I am unable to view the first target larger when clicking on it. The second one is fine as is the one in the next post. Could you upload the first one again please?

Andrew Leigh
May 7, 2013, 03:41 AM
Ok Doc,

Firstly nice shooting. My initial observation would be that your last load at 42.4 is approaching the accuracy node.

The way you have triangulated it correct but unfortunately it would appear as if you have not yet reached the accuracy node which I believe is closer to the 42.4gr. You should have been around the 2900fps mark?

Unless you had signs of pressure you may have stopped the process a little short in terms of the load. That is why I load over by two or three load increments, these may not be fired if there are signs of pressures or if the velocities exceed allowable limits.

If it was me, and had I not observed no signs of pressure, I would load 5 each of 42.0 / 42.4 / 42.8 / 43.2 and throw those down the range after the mandatory three fouling rounds. 5 because you can then compare them to where you were as you were able to pop three into one hole with your previous load lets see if the other two don't fly. Have you a beam scale to throw these charges with? I think that you may well settle on 42.4 or 42.8. The 120gr. Sierra SPT has a maximum vargret load of 43.8gr (according the the Sierra Infinity Software) so you should be OK.

On the fouling rounds may I suggest that you load them at 42.4gr. and shoot them on a target to see if, with the once formed brass and the slightly larger load, wheather the first round still prints as high. That way you can kill two birds with one stone.

That last two groups are great, looks like .75 and 0.50" respectively, these in my opinion are approaching or at the accuracy node, we need one or two groups on the other side to see if they get better or open up again. The final two loads POI print almost on top of each other which is great.

Generally it would appear as if the brass has made a difference, do you concur?

Did you happen to measure velocities or not, it would appear as if your std devaitions have improved.

How are you feeling about the latest round, do you feel like you are getting anywhere or just going around and around? The 5 shots groups will be telling.

Cheers

docsleepy
May 7, 2013, 05:26 AM
Here is the first set of groups (lowest powder charges) uploaded again:

docsleepy
May 7, 2013, 05:37 AM
Ok Doc,

Firstly nice shooting. My initial observation would be that your last load at 42.4 is approaching the accuracy node.

The way you have triangulated it correct but unfortunately it would appear as if you have not yet reached the accuracy node which I believe is closer to the 42.4gr. You should have been around the 2900fps mark?

Unless you had signs of pressure you may have stopped the process a little short in terms of the load. That is why I load over by two or three load increments, these may not be fired if there are signs of pressures or if the velocities exceed allowable limits.

If it was me, and had I not observed no signs of pressure, I would load 5 each of 42.0 / 42.4 / 42.8 / 43.2 and throw those down the range after the mandatory three fouling rounds. 5 because you can then compare them to where you were as you were able to pop three into one hole with your previous load lets see if the other two don't fly. Have you a beam scale to throw these charges with? I think that you may well settle on 42.4 or 42.8. The 120gr. Sierra SPT has a maximum vargret load of 43.8gr (according the the Sierra Infinity Software) so you should be OK.

On the fouling rounds may I suggest that you load them at 42.4gr. and shoot them on a target to see if, with the once formed brass and the slightly larger load, wheather the first round still prints as high. That way you can kill two birds with one stone.

That last two groups are great, looks like .75 and 0.50" respectively, these in my opinion are approaching or at the accuracy node, we need one or two groups on the other side to see if they get better or open up again. The final two loads POI print almost on top of each other which is great.

Generally it would appear as if the brass has made a difference, do you concur?

Did you happen to measure velocities or not, it would appear as if your std devaitions have improved.

How are you feeling about the latest round, do you feel like you are getting anywhere or just going around and around? The 5 shots groups will be telling.

Cheers

Thanks.
Wow, this is getting into "hot" loadings! I had previously avoided them to increase brass life. I HAVE had some pressure signs at these charge levels, just on hot days (85 F) -- yesterday was cool (60's 70's F).... Willing to give it a go a bit here; accuracy node should move to lower powder charges on summer days and I can adjust.

My next chance to try several loads won't be until next weekend or later.

Was not able to measure velocity--wind & shots knocked over my sun-diffuser. Perhaps we'll have a cloudy day by luck.

On the brass/velocities -- this is ironic to me. The only changes I really made were to
a) individually measure each load rather than using powder thrower
b) pay more attention to bullet seating depth (probably the key element, since I was loading right around the lands' depth)

Things do appear to be doing well, and I did think those last two loads' POI were nicely on top of each other!

I'll try the foulers at the same level and see what happens (that would be nice!).

The new Shilen match barrel should be on its way at some point.....things should be MUCH better then.

Andrew Leigh
May 7, 2013, 06:31 AM
Hi

The barrel may be an improvement but nothing like a problem to focus the mind on the basics again. Still 0.5" is nothing to be sneezed at many would give a delicate part of their anatomy to do that:).

My first hunt this year is planned for 26th June to the 2nd July. I will need to get out onto the range myself soon.

I have 3 accuracy nodes on my 6.5mm but generally load to the the middle one. As we will be going for Springbuck (amongst others), I wanted to chase 120gr. in the 6.5mm hard to get minimal drop over distance. These are little buggers normally shot at 200m+.

Looks like you may have a node at 40.8gr.

I am a hunter so my loads genearally tend to be conservative, a nice slowish 180gr in the 30-06 and a 140gr slowish in the 6.5mm assures minimal meat damage. Not normally in favour of shooting a grain of rice at the speed of sound.

docsleepy
May 7, 2013, 11:20 AM
You asked about scales. The only mechanical scale I have is the diminutive Lee powder scale. I generally trust the RCBS charge master. I have a cheap MTM scale and it agrees within 0.1 grain almost always with the Chargemaster.

ironworkerwill
May 7, 2013, 02:02 PM
I have good faith in my Lee scales. I have 2 electronic scales that wont hold a candle to the Lee. I will usually throw close to the target load then use a trickle to pin point.

popper
May 7, 2013, 04:13 PM
It's bore condition on the first shot. Grease makes it more consistent. You push the junk out on the first shot, what ever that junk is, in a dry? bore. Good old coefficient of friction. If you consider that ~20% of the energy in each shot goes to heating the bbl, you will be surprised to see how hot the bore actually gets. Mosin doesn't do it cause it's an old well used bbl, i.e. more clearance between the bore and jacket.

docsleepy
May 7, 2013, 07:41 PM
It's bore condition on the first shot. Grease makes it more consistent. You push the junk out on the first shot, what ever that junk is, in a dry? bore. Good old coefficient of friction. If you consider that ~20% of the energy in each shot goes to heating the bbl, you will be surprised to see how hot the bore actually gets. Mosin doesn't do it cause it's an old well used bbl, i.e. more clearance between the bore and jacket.

ironwokerwill: Gee, maybe I am selling my Lee scales short! Have you compared them with the RCBS chargemaster scale? Everytime I weigh something known (like a bullet) on one of my digital scales, they come up exact. I write the weight of the little plastic cup on it, as a check, and it is perfect every time. So I had assumed the digital scales were good to 0.1 grain or better. I think the Lee is probably there also. Is one better than the other?

popper: Wow, I had never thought of that. Putting together what you point out with what hammer previously explained, and I think we are MUCH closer to understanding! I did some math, using Q=mC(delta T), [heat = mass time * specific heat * change in temperature, from high school chemistry ] assuming a 1.5kg barrel of chrome-moly (.456J/g deg C). A 2000 ftlb bullet is 2700 J I found, and taking 20% of this I found that the barrel might gain 1 deg C per each shot. That seems reasonable, in fact it might be more than that, so indeed, 20% -- or more -- of the energy is going into the barrel!! If the coefficient of friction is altered by dried-out carbon residue, then it could be significantly more friction. That agrees with a lower velocity measurement I found on one shot. The grease would reduce the coefficient I would expect.

I checked, and yes, smokeless gunpowder [smokeless means products are almost completely gasseous, whereas black powder products maybe 50% solids] does have hydrogen and oxygen --hence should produce water (vapor). That means any unburned powder or ash (although minute, but present, we know, from patching our barrels) will have some water component -- which could become drier or wetter over time depending on ambient humidity---and thus change the initial friction.

A change of velocity of 50 fps (similar to what I've observed on 1st shot) is on the order of 100 ft lbs, or maybe 150 J. If the barrel is already absorbing 500 J or more, it is very reasonable to think that there could be a change in the coefficient of friction sufficient to change that energy loss to 600 or more J due to dried residue!!

So this is making a lot more sense.

docsleepy
May 7, 2013, 07:45 PM
Grease, with a lower vapor pressure, lasts a lot longer than oil. I'm wondering what would happen if I ran a lightly greased patch through the barrel after every shot (to remove the ash products and leave a consistent film) and repeated within a few hours of the first shot of the day. Wonder if that would make the coefficient of friction similar for every shot???

docsleepy
May 7, 2013, 07:49 PM
The Mosins get shot with anything from very loose (.308) to tight (.311) to very tight (.312) bullets.....but having put a BUNCH of bullets thru them, perhaps they are more lapped???

And some barrels might have a better lapping, or be shot with different powder making different ash -- and some with tighter or looser bullets -- this may explain why some barrels see higher or lower velocities.

Now I still don't understand why a LOWER velocity makes for a HIGHER bullet....but maybe I am on a different node and the barrel ring explains it?????

ironworkerwill
May 8, 2013, 11:19 AM
Doc I've never used the Chargrmaster. But, I don't have full confidince in powder throwers for precision shooting. They will be close enough for hunting or plinking and usually do well for pistol. Consistancy, however, is what we want for those one hole groups. I weigh every thing. To the 1/10gr or better on powder and bullets, then within reason on brass. Brass is sorted on number of uses, brand, and method of sizing.

Confidence is a factor in shooting. There are very good beam scales available that you may feel more confident using. RCBS, Lyman,and Hornady all make good ones and they look more like precision tools, unlike the plastic Lee. The analog beams will be close to the arrow and not "spot on" and one individual grain of powder may make the difference getting the marks to align. My digital scales will not notice one individual grain. As both digital scales are accurate to .1gr and one individual grain weighs less than .1grain it is not designed to read such a small ammount.

I got my first digital scale(elcheapo) for speed and soon realized it would not weigh the check weight consistantly to .1grn. I now use it for brass. The second digital(brand name)scale will weigh the check consistantly but it is a liar.


I've never had a box of sierra bullets (my usual brand)that were all exactly the same weight. They vary +-.5gns as a whole 100ct box. Such as the last batch of game kings. The heavy side was 160.4 and light 160.0 and there was close to 40 bullets that weighed 160.2.

kelbro
May 8, 2013, 02:09 PM
Try running a patch with LockEze on it down the bore. Makes my first shot hit where #2 and #3 hit.

docsleepy
May 8, 2013, 03:03 PM
Ordered some lock-ease from amazon. I'm testing so many things at the same time, I'm not sure what I'll get to it but it makes sense. From what I read it is a graphite product. Basically carbon.

As far as the beam scale. It really makes sense that I might pick up a really nice being scale, Maybe an rcbs. What I don't understand, is why it makes so much difference? On my digital scale, I think I counted and about six granules of Varget equals one 10th of a grain. Don't quote me on that, I'm just trying to remember. So I won't argue for a minute that my digital scale could easily be off by one half of one 10th of a grain, or maybe even a 10th of a grain. But you guys have me doing this optimal charge weight. The data from the previous tests, see pictures above, shows that 4/10 of a grain made less than a quarter inch difference at the optimal position. For hunting, I would like to be under an inch, and always ALWAYS under an inch even on the first shot. So, can you help me understand why a tenth of a grain error is that important? Additionally, I've read on several benchrest threads, that people use throwers or digital. I've got a six PPC Benchrest that will group around 3/8 of an inch or better using a thrower. So?? Not trying to be argumentative, just trying to understand. Those RCBS beams sure look nice!

ironworkerwill
May 8, 2013, 03:27 PM
I have a feeling that you're doing right by getting a new tube. Some factory barrels are more forgiving than others. Buy 2 identical rifles and chances are one will shoot better with a specific load than the other. As well, one will be more forgiving as far as charge consistancy, type of powder, bullets ....ect. One barrel could have been chambered with a new reamer and the other with a reamer thats about to be worn out but is within tolerance. The list goes on.

In summary, the pickey rifle will make you a better handloader.

docsleepy
May 8, 2013, 04:01 PM
You're right about that!

balderclev
May 8, 2013, 06:16 PM
This is an excellent article about accuracy from the experts.

http://www.angelfire.com/ma3/max357/houston.html

docsleepy
May 8, 2013, 06:59 PM
Thank you very, very, very much! That was an amazing article.

Jesse Heywood
May 8, 2013, 10:55 PM
I am not an expert on accuracy. If I hadn't gone to kindergarten I couldn't spell it!

My thought is that you need to stop making multiple changes. The only way to prove anything scientifically is to make only one change at a time. It seems like the long way to figure out a problem, but patience is a virtue.

Lock-eze is simply graphite powder suspended in an evaporative carrier. The carrier dissolves the gunk in the lock tumblers and the graphite is a dry lubricant. Most hardware store carry Lock-eze. A patch with a little solvent followed by a dry patch with a little dry graphite should do the same thing, Lock-eze would make it a little easier.

docsleepy
May 8, 2013, 10:55 PM
The .308 Hornady Match cases I ordered (when they showed on Midway site) are on their way. Midway is now showing "out of stock, no backorder" unknown next availability.....

I did find military brass from www.brassreload.com with various grades and prices, and AVAILABLE. I'll use that to help out friends. Holding a "reloading " party has become the hit thing to do in my church.

ironworkerwill
May 9, 2013, 12:50 PM
Norma makes really good 7-08 brass. I think it is around $28 (25 count),when you can find it.

Nice link Balderclev!

ngnrd
May 9, 2013, 06:04 PM
...So now, will change the barrel. ...

Just a quick logic check here, guys.

Does it make any sense to go through all the machinations of working up loads and trying to decipher the "first shot high" issue, if a different barrel is going to be installed anyway? Just seems like a waste of components to me.

docsleepy
May 9, 2013, 08:11 PM
My thought is that you need to stop making multiple changes. The only way to prove anything scientifically is to make only one change at a time. It seems like the long way to figure out a problem, but patience is a virtue.

Lock-eze is simply graphite powder suspended in an evaporative carrier. The carrier dissolves the gunk in the lock tumblers and the graphite is a dry lubricant. Most hardware store carry Lock-eze. A patch with a little solvent followed by a dry patch with a little dry graphite should do the same thing, Lock-eze would make it a little easier.

Multiple changes are a problem, agreed. The advantage here is that I can try the Lock-eze on the first fouler shot and by the 4th fouler, it won't matter and I can continue the OCW process recommended by another writer.

You're probably right that I could have found lockeze at a hardware store. Dumb me. But it is coming.

As for worthiness of investigating -- yeah, I wouldn't put TOO much effort here, but I am learning and I have a bunch of other rifles that could benefit from anything that I figure out here! This rifle has always given me more fits, and I figured I had little to lose by experimenting on this bore. Thankfully I have relatively abundant components (am actually bringing up multiple new reloaders up to speed at same time). New barrel expected around June 1, so we'll see what I learn by then. If we figure this one out, then it may be useful to someone else among my friends.

docsleepy
May 9, 2013, 08:13 PM
May be able to do the higher-end round of OCW tests Saturday. Busy until then.

I use Norma brass for 7.62x54R and yes, it is great. Somehow I got Hornady for this rifle and wnated to stick with it.

ngnrd
May 9, 2013, 09:24 PM
As for worthiness of investigating -- yeah, I wouldn't put TOO much effort here, but I am learning and I have a bunch of other rifles that could benefit from anything that I figure out here! This rifle has always given me more fits, and I figured I had little to lose by experimenting on this bore. Thankfully I have relatively abundant components ...

That's reasonable, I suppose. Good luck with the diagnosis.

Andrew Leigh
May 10, 2013, 01:08 AM
Just a quick logic check here, guys.

Does it make any sense to go through all the machinations of working up loads and trying to decipher the "first shot high" issue, if a different barrel is going to be installed anyway? Just seems like a waste of components to me.
Yes,

nobody knows definitively if the barrel is poor and secondly working up loads is an art that needs to be practiced and honed. Already the method being employed has discounted some loads and homed in on a load producing 0.5" groups, nothing to be sneezed at.

The OP is also experimenting with a different load development method. If found to be unacceptable then this method will be discarded, if good this routine will add value to his shooting experience.

ngnrd
May 10, 2013, 04:29 PM
nobody knows definitively if the barrel is poor
True. But we do know that the barrel is going to be replaced. And changing the barrel will certainly change how the rifle shoots. So, I would think that new load development would be necessary for the new barrel.

And, while I agree that gaining knowledge about load work up in general is important, I didn't see any real benefit in doing a workup for this particular rifle, only to have to start over when the barrel gets swapped out.

But, docsleepy wants to do it. And, who am I to judge how he uses his components and his time? I just thought I'd throw it out there.

Carry on. Nothing to see here.

docsleepy
May 10, 2013, 10:14 PM
1. Unable to find Lock-ease at Lowes (surprised me!), some is on order from Amazon. I will try to dissolve some lock graphite into some Butches Bore Cleaner or something similar. It might dissolve in rubbing alcohol. All I need is some vehicle to carry it and then vaporize. If that doesn't work, I'll try the two-patch idea.

2. Gee, if I could get this barrel to WORK, it might be useful to me or to a friend who has a savage gun of any type.

3. The reason I decided to embark on this investigation was that I had worked with this barrel for twelve months, and I was very familiar with a very repeatable first shot problem. If THIS barrel could be made to work better, I would have a huge knowledge tool at my disposal to assist in other guns where changing the barrel isn't so much of an option! I would probably try the same solution on higher-caliber AR's and see if they got even better.

4. I'll anneal some brass, create the loadings and if possible get some tests done tomorrow before it heats up here. No clue whether I'll be able to get the chrony to work, it is supposed to be sunny.

5. The "first shot" tests will be separated from the "OCW" tests by several foulers, so they should be relatively independent tests. As andrew suggested, I'll use the hotter loadings for the foulers. Sure would be nice if I could get at least some accurate chony readings.......

6. I got in some once-shot military .308 brass, but am still waiting on more Hornady .308 Match (my preferred).

docsleepy
May 11, 2013, 03:17 PM
Here are the data from today.

Reloads:
1. Had to toss another 4 cases for incipient head separation discovered with bent paper clip.
2. Moved FL sizer maybe .002-.004 tighter based on measurements suggesting I was bumping shoulder back .005 (more than necessary)
3. As before, annealed, dried, lubed, FL sized, trim, chamfer, smooth, neck size, prime, charge (Varget, Chargemaster), seat. Press closed twice on seater die (found this makes for more consistency) and then all bullets checked with Hornady 0.28" comparator, 2.260-2.265 tolerance. 2 or 3 were long, once more in the seater die and they shorten up nicely by a couple or 3 thousandths.
4. Clean off lube.

Shooting:
100 yards, 80 F at start, 85 F at finish, took breaks between each "round robin" sequence. 16X scope, Rock BR front rest, rear leather bag, firm hold into shoulder pocket, forend in U-shaped wooden "shim". Foulers fired until two at approx same level. Foulers 42.8 grains Varget. Thankfully, there was some cloud cover and it was before noon and my Chrony was in some shadow and it WORKED!

Cleaning:
Mixed Hoppes 9 and lock graphite in small container, soaked a patch, ran down bore (bore guide) multiple times. Then put graphite on a dry patch, ran THAT down bore (bore guide) multiple times. Then used short rod and clean patch to clean chamber of any material.

There was variable wind in the 5mph range.

Displays:
Foulers are at left hand frame
Inch marks are visible in all targets
Red dots mark what I think is the geometric center of acceptable shots in each powder test
Composite geometric centers on the far right.
Measured velocity is right beside each shot.

NOTE: I had three rounds of ammo that were clearly not quite FL sized enough and closing the bolt required a push. I have marked these shots with "starburst" and because they uniformly shot LOW I have eliminated them from consideration. I think I've seen this before with this barrel, but these structured tests really brought it out.

NOTE: primer flattening increased noticeably at each higher charge and slight "volcano cratering" of the primer indentation occurred at the two highest charges.

docsleepy
May 11, 2013, 03:20 PM
COMMENT ON INADEQUATELY FL SIZED CASES:

Wow, normally one expects "tight" cases to be MORE accurate! I'm guessing that this means there is some error in my cheap barrel's chambering -- some assymmetry in the shoulder-to-bore alighnment or something.

My conclusion is that I'll probably re-adjust the FL sizer back down .002" to be certain that the bolt can easily close on all cases, because this seems to be a huge effect!

docsleepy
May 11, 2013, 09:01 PM
1. I'm loading very close to the lands, which increases the pressure. I'm using a 22" barrel - shorter than what most loading books use. Sierra lists max velocity with Varget, 120grain bullet as 3000; Hodgdon lists 3117 fps. Likely by 42.0 grains I am at max pressure and the loads above this should be avoided if possible. (Note I did see progressive flattening of Winchester LR primers)

2. Given the higher tempperature, the 41.6 load of today's data probably compares to the 41.2 gr of previous data (and note their vertical position is similar). Possible accuracy loading for summer might be 41.6, for winter 42.0 or slightly more. What do others think?

3. The geometric centers above 42.0 grains just make a circle -- probably because they are all statistically "identical" (impossible to separate with only 3-4 shots per group.

4. Note for this test, today, at least, the graphite regimen didn't perform very well for reducing the first shot error. With very few tests, the grease so far seems slightly better. Interesting that the first shot was indeed slower, again.

5. Something about what happens when the case is JUST slighltly too long--does it hit an assymmetric junction between shoulder / neck / leade of the chamber and BEND the case? Best thing I can think of to explain the wild shots is that the bullet got started aimed slightly off center.... Any other theories?

Andrew Leigh
May 12, 2013, 03:28 AM
Hi doc,

Accepting that the barrel is possibly poor and will be replaced I would now agree with ngnrd, perhaps it would now be prudent to back off on load development as I believe that there are two major variables at play. The one is the barrel and the other is the handloads themselves. Lets remove the one major variable first, the barrel.

Clearly your results prove that inconsistencies in case prep results in large inconsistencies in POI. I think that there are anomalies in the handloads and that these probably exist in the case preperation. The cases may well be past their sell by date through overannealing / overworking. You also experienced case seperation and mentioned three rounds resulted in hard bolt closing yet another indication of inconsistent case preperation.

Why are you FL sizing and then neck sizing?

The target at 42.8gr. has only 2 shots on it, am I correct?

When you get the new barrel I would start with brand new unfired brass, this will give at least four reloads before any annealing needs to take place. I anneal after every 5th time the cases are fired, you seem to anneal each time you load?

docsleepy
May 12, 2013, 05:39 AM
Andrew -- thanks for your consistent attention

1. The target at 42.8 has 3 shots, but you wouldn't know it because the group has opened up so much! The 3rd shot is way over to the right, at the next group's left edge of bullseye. By this point, the velocities are WAY over what Sierra lists as their maximum velocity for max load.

2. I'm fascinated by the concept of "over" annealing. Annealing should return the metal to an initial state. Repetitively annealing should not be able to return the metal domains to any "pre" initial state. I have had zero failures of the annealed neck; no cracks, and certainly no blowouts. These cases are certainly past 10 reloads and may be approaching 20. The incipient head separations are occuring consistently about a cm from the head. (bright line on outside, noticeable "dip" when feeling with the bent paper clip on the inside surface)

3. Why both full length AND neck size? Because many believe that the expander plug in the FL sizer contributes greatly to poor concentricity, and that neck sizing reduces this. In my case, I believe it reduces neck tension somewhat (I say that because I can feel the resistance as the mandrel enters the neck, so it apparently expands the opening a bit) and hopefully brings them all to a more constant tension.

4. There were 3 cases that ended up "long" and were difficult to chamber, (required maybe 5 lbs force on bolt) but other than that, the velocities appear very tightly grouped, right? (I think the one velocity in the 3200's is probably an error either of the chrony or of my recording). On this die, about 5 degrees in the bushing will set the die .001" shorter (more) FL sizing, so I had turned it out by 10 deg (.002) -- that resulted in some too-long cases as I'm closer to the edge than I realized... Will move it back where it was.... I was trying to get even more case life by doing absolutely minimal sizing as many suggest bumping shoulder back only .001" I should order a headspace cavity to allow more accurate measuring....

5. Good news -- two boxes of new cases arrived in the mail just after I left for the range, so I have plenty of new cases for trials with the new barrel when it arrives.

6. I should do a comparison of annealing every reload versus annealing every 4th reload and see what is the difference! It certainly is a lot of work!

7. The velocities I reached are beyond those of either Sierra or Hogdgon max-pressure velocities, and at the top, the Winchester primer flattened across its entire diameter and the firing pin indentation began to have a raised edge where it forced metal around the firing pin. These have nothing to do with the CASE, but indicate I am well into metal-deformation pressures, right? The only time I have gone any farther into high-pressure land was with a 6PPC and stout brass -- I would expect the possibility of real primer cratering and or pieced primers within a few more steps, right? (I had a few pierced primers once in the 6PPC rifle)

docsleepy
May 12, 2013, 05:55 AM
The good news for me, in my estimation was the following:

The change in the (3- or 4-shot) group center is, in the region of 41.2-42.0 grains, moving only 0.25" for a change of 0.4 grains. That means that the variation in point-of-impact for a charge error of 0.1 grains (the accuracy of the Chargemaster) is now in the range of 0.06", which is inconsequential in hunting deer! The errors of the barrel (it appears to be a 1-MOA or slightly better at times $85 factory pencil barrel) appear now to dwarf the powder charge aspects.

Possibly adjusting the seating depth would bring about a further reduction in group size, if further improvement were warranted.

But the FIRST SHOT problem (2" with the graphite, maybe 1" with the grease in very small number of trials so far!) is a much bigger hunting problem, unless you have deer that will hold still while you fire a fouling shot!

docsleepy
May 12, 2013, 07:30 AM
Attempt to allow you to see the primers. Iphone will focus only so closely, and no more.

Note the nice rounded edges on the unfired primer (farthest left).
The 41.6 charge still has some remaining rounded edge.
By the time you get to the 42.8 charge, the rounding is gone, the primer is just about completely flattened, and you can see that it is filling out much of the beveled primer pocket entry area. This means (I think) that the metal in that area was impacted by sufficient pressure to allow plastic molding.

These are Winchester LR primers.

docsleepy
May 12, 2013, 07:31 AM
The entire group at once

Andrew Leigh
May 12, 2013, 12:38 PM
Andrew -- thanks for your consistent attention

2. I'm fascinated by the concept of "over" annealing. Annealing should return the metal to an initial state. Repetitively annealing should not be able to return the metal domains to any "pre" initial state. I have had zero failures of the annealed neck; no cracks, and certainly no blowouts. These cases are certainly past 10 reloads and may be approaching 20. The incipient head separations are occuring consistently about a cm from the head. (bright line on outside, noticeable "dip" when feeling with the bent paper clip on the inside surface)

You CAN over anneal. The three stages of the annealing process that proceed as the temperature of the material is increased are: recovery, recrystallization, and grain growth. The first stage is recovery, and it results in softening of the metal through removal of primarily linear defects called dislocations and the internal stresses they cause. Recovery occurs at the lower temperature stage of all annealing processes and before the appearance of new strain-free grains. The grain size and shape do not change. The second stage is recrystallization, where new strain-free grains nucleate and grow to replace those deformed by internal stresses. If annealing is allowed to continue once recrystallization has completed, then grain growth (the third stage) occurs. In grain growth, the microstructure starts to coarsen and may cause the metal to lose a substantial part of its original strength. This can however be regained with Hardening.(Wikipedia)

The problem is that you NEVER know how much to harden to get the case back to optimum but by limiting temperature and time you can keep the annealing process within an acceptable band. You are grossly overworking your brass by the sounds of it. Over annealing and then over processing to get it hard again.

3. Why both full length AND neck size? Because many believe that the expander plug in the FL sizer contributes greatly to poor concentricity, and that neck sizing reduces this. In my case, I believe it reduces neck tension somewhat (I say that because I can feel the resistance as the mandrel enters the neck, so it apparently expands the opening a bit) and hopefully brings them all to a more constant tension.

I have never had good results with neck sizing. I am not for one minute knocking the technique but just stating that I cannot get a consitent neck tension. I would recommend that you do the one or the other.

4. I should order a headspace cavity to allow more accurate measuring....
I would agree.

5. Good news -- two boxes of new cases arrived in the mail just after I left for the range, so I have plenty of new cases for trials with the new barrel when it arrives.
Do not anneal until at least after the fourth firing.

docsleepy
May 12, 2013, 02:33 PM
Hi Andrew!

We'll give it a whirl your way!

Thanks for the insights!
After yall's concerns, I just FL sized ONCE for the last two or three sets of tests. When annealing, I use a very dark room (only during nighttime) and don't start until I can recognize certain cans in the dark. Then I stop as soon as ANY discernible dark red glow is appreciable and dunk in water. Thus time/temperature is limited.

Certainly worth trying the new brass with much more limited annealing. It can then be compared with some of the many many timed used brass and I'll learn even more.

I'll probably hold off for now until the new barrel arrives, as I think I've learned the majority possible with the old barrel.

You didn't comment on the velocities or the primers?

Andrew Leigh
May 12, 2013, 03:10 PM
You are a very hot, as mentioned the Sierra sofware had the Varget load for the 120gr at a max of 43.8gr to give 3000fps. At 43.2gr you are close to 150fps hot, discounting the extra 0.6gr you are still about 100fps hotter. At 42gr. you should be under 2900fps and your are at 3100. This all for a 26" barrel, the fact that you have a 22" barrel make these loads even more scary, you can add about 120fps to existing loads to bring them back to a 26" barrel. Conversely you should be shooting 3000fps - 120fps at max load.

What is your jump to the lands, it seems like you are shooting off the lands creating undue pressure? Your OAL should be 2.780".

The primers at 42.4gr still look OK. Did you have any hard bolt opening problems?

docsleepy
May 12, 2013, 05:57 PM
Hi,

Yes, for these tests I SHORTENED the COAL by .010 to get it off the lands somewhat -- I was previously right on the lands. I do believe that I am way over pressure, which is probably why the velocities are beyond book value even for a longer barrel.

There were two or three "not perfectly easy" bolt openings, but nothing that required a 2x4. I was pretty convinced the highest and next highest loading were over pressure and that is one reason that I ddin't do the 4th shot at each.


What I've read before in 6PPC is that when you go overpressure, the groups will tend to blow out, and it seemed to me that I saw this in the next-highest pressure group.

The first three shots in the 41.6 group were a cloverleaf. Given the increase in temperature (80-85F) , these are probably comparable to the 42.0 set of my previous tests (at 60-70 F) -- and that set was the 0.5" group. Sure seemed that this particular pressure/velocity was optimum for that barrel -- would need to adjust the powder based on ambient temperature to achieve that group.


Did you see in the article someone referred to us that they stated that loading into the lands was an absolute requirement in all their experience to get the best accuracy? They were regularly achieving 0.030" groups, and considered 0.2" an utter failure.

docsleepy
May 12, 2013, 10:07 PM
y'all got me thinking about annealing. Found this temperature guide:

http://www.reloadersnest.com/forum/topic.asp?TOPIC_ID=20330

480 Barely red in the dark
600 Dark red
800 Cherry red
950 Orange, barely visible in sunlight
1100 Orange-yellow, visible in bright sunlight
1300 Light yellow, nearly blinding, welding goggles required.
1500 Nearly white, blinding

I use a dark room (one neon bulb night light behind my back, wait until I can see certain cans on a shelf in the dark) then stop as close to barely red-dark red as I can, which would be 480-600 from the above chart.

http://www.6mmbr.com/annealing.html
Is a helpful article on annealing, several lower down on the page seem to use the same technique (I bet it is where I got it front, I surely didn't think it up myself). There are some interesting statements in that article.

I'm very interested to see how this will go with much less annealing. Will surely be a lot less work on me! With my 6PPC/turned necks, I never annealed. When I first started working on the 7mm08 I noted continuously worsening groups....and then I tried annealing and suddenly the groups tightened up dramatically (shot a 10 shot group that astonished me that day). But perhaps I'm going too far.

Andrew Leigh
May 13, 2013, 01:03 AM
Did you see in the article someone referred to us that they stated that loading into the lands was an absolute requirement in all their experience to get the best accuracy? They were regularly achieving 0.030" groups, and considered 0.2" an utter failure.

No problems with loading into the lands, just make sure that load development starts well down the scale. Some bench guys seat long and so lightly that they actually "seat" the bullet into the lands when they chamber.

The rifles they speak of have substantially better actions and barrels than the off the shelf rifles, so for lesser mortal like me one hole groups remain the Holy Grail. The one guy they mentioned had such a close fitting action that re-inserting the bolt was a mission as the tolerances were so tight that one needed perfect alignment for the bolt to enter the action.

docsleepy
May 13, 2013, 05:30 AM
The results that I achieve around the 41.6 and 42.0 area are plenty good enough for my intended use (deer, up to 300 yards). The variation in average point of impact was less than 1/4" for 0.4 grain differences. I can use 41.6 for hot days, 42.0 or 42.2 for cold days.

Now the remaining problem would be the 1st (cold) shot error. In the remaining time prior to the new barrel, I may give some more tests of grease (a new tube arrived) versus graphite -- or maybe mix the two together?


Midway's email says the 7mm08 and 6PPC case gauges have shipped.

balderclev
May 13, 2013, 10:04 AM
I remember that there is something that welders use to control temperature when heating steel. If I remember correctly, it is rubbed on the steel and melts at a certain temperature. There are several variations of it that melt at different temperatures. Wonder if that might help in annealing.

docsleepy
May 13, 2013, 11:38 AM
http://www.nissenmarkers.com/catalog/Category/Temperature-Indicating-Sticks

Found them. Reasonably priced also. I may give this a try!

Andrew Leigh
May 13, 2013, 02:11 PM
Gunshops sell a product which you paint on and it indicate the temperature.

Tempilaq and Tempilstick

BullfrogKen
May 13, 2013, 09:27 PM
Forgive me, but if you're going through all this hassle for deer - loads for cold days, loads for warm days, annealing the literal life out of your brass, seating into the lands chasing after benchrest accuracy. . .

You're not paying attention to the right things. You've totally lost yourself in the weeds of extreme accuracy only necessary for benchrest matches when you don't need it. Especially at 300 yards.

Learn to judge range and dope wind. Or just buy a laser rangefinder and learn to dope wind.

savanahsdad
May 14, 2013, 12:43 AM
Gunshops sell a product which you paint on and it indicate the temperature.

Tempilaq and Tempilstick
yes, only 166 post to get through to get to the right way , it is TEMPILAQ TEMPERATURE INDICATOR , $21.99 per 8oz , in stock at midwayusa.com, right now. I use the 750 deg but I only use it on old cases like 32rem, or any thing I know to be 20+ years old, I have never done any of my 7mm-08's ,all of my 7mm-08 are Rem7-08 cases and are at 10+ loads , I get sub 1MOA with my Savage mod 16. in 7mm-08 new in 1997 it got 1.75MOA out of the box with factory ammo after I gave it a tune up and my hand loads added to the mix, it now shoots 1 to .75 MOA, some days a bit high and some days right on but the first 5 shots hit under 1" .I say as other have. stop annealing , brass that is too soft will losse it's grip ,

docsleepy
May 14, 2013, 01:16 PM
"You're not paying attention to the right things. You've totally lost yourself in the weeds of extreme accuracy only necessary for benchrest matches when you don't need it. Especially at 300 yards."

I think there's a lot to be said for this!
My major concern is the first shot error. 2 inches at 100 yards turns into 6 inches of 300 yards, and add a bit of new hunter anxiety, and you've got a deer that I missed.

The grease trick seemed to reduce the error on the first shot significantly

There seem to be a lot of misconceptions about annealing. Here's a quote from 6mmbr.com: "The smallest 1000-yard 5-shot group ever shot in IBS competition was done with brass annealed after every firing."

At least in my experience, annealing increases rather than decreases neck tension. You can certainly feel it when you pass the Lee mandrel into the sized brass. Certainly, this level of effort, it's probably overkill. But since some members felt like a optimum charge weight test was needed, best to be sure that the brass all has good neck tension. I learned this the hard way, early on with this rifle, that multiple times shot brass would begin to not even hold the bullet.

Sure wish this rifle would put five shots inside a quarter on the first five shots! It certainly can do that after the first couple. Still looking for ideas on what's wrong with that first shot. Any good ideas?

docsleepy
May 14, 2013, 01:18 PM
I did buy the laser rangefinder quite a while ago. Good purchase.

docsleepy
May 15, 2013, 05:53 PM
Progress is being made!

This is today's cold-shot test (can only do ONE each range trip....). I went to a 300-yard range, measured the MOA of the various dots on my scope reticle by comparing to a known measure at 200 yards, adjusted my aim accordingly by the dots to account for a 2.5 MOA drop at 300 yards compared to my 1" high zero at 100 yards (see previous photos for 41.6 grains Varget) and let 'er rip!

Cold shot at 300 yards is well within a deer kill zone, 1.25" above bullseye! This was just about exactly the shot I missed last fall.

The 2.5 MOA drop estimation comes from entering in all the particulars into jbmballistics.com since I now have oodles of data on this bullet and this load thanks to all the OCW tests.

The barrel prep I used was the "grease patch" one: Over and over and over I ran a greased patch down the barrel (using a bore guide to protect the chamber), and finished by a clean patch only in the chamber.

I then proceeded to take out 4" clay pigeons (another proxy for deer kill zone) one after another on the same berm.

(The lower bullet hole in the target is my "cold shot" from a Rem 6.8SPC. )

This is huge for me. Thanks for all your advice, guys!

Andrew Leigh
May 19, 2013, 01:43 AM
Hi Doc,

as a matter of interest I went to the range yesterday to develope a 120gr. load for my 6.5mm. As a matter of course I always fire my fouling shots into the butt but given your experience I fired them on target just to see what the first "cold" shot did.

To my surprise I shot a three shot group of 0.39" on POA. The best goup I have EVER shot with a hunting rifle to that point. Oddly enough my first OCW load was at the same powder charge and the group opened to 1.5", just goes to show what shooter inconsistency does.

Another observation was that I was using S&B cases which I forgot were inconsistent and that the shoulder was not where I needed it to be. These I had put in a box to discard but it has been a while since so I forgot their fate, my bad. My Chrony results were awefull which I put down wholly to the brass. The std dev's went from 4.6 to 42.7.

I had specially bought Lapua brass for the exercise which I did not use. Note to self, chuck brass you want chucked immediately and crush the necks so you can't reload them and use decent brass.

Despite that the 6.5 was awesome, also picked up that the action screws are a little loose as I was getting horizontal stringing. Our winter are so dry that stocks "shrink" a little during this season and one must be mindful to tweak the screws.

Had two accuracy nodes which need to be varified when I load with better brass, the group of the day was 0.37" which at 100m (metric land) is 0.32MOA. I am super chuffed.

docsleepy
May 19, 2013, 02:37 PM
Who made the barrel? Pretty good rifle I would say!

Didn't you have a hunting trip recently? How didthat go?

Andrew Leigh
May 19, 2013, 02:52 PM
It is a CZ550 that I bought brand new.

I have a trip for the 26th June to the 2 July on my friends farm in the Eastern Cape and another one on the 29 to 21st August in the bushveld of the north. Will let you know how it goes.

ottsixx
May 20, 2013, 09:44 AM
cold clean barrel does it every time or it has for me anyway.

docsleepy
May 23, 2013, 06:18 PM
The NEW SHILEN barrel arrived EARLY! Wasn't expected it until next week.

Just ordered a precision barrel nut to go with it. That will be coming priority mail. Perhaps over the weekend....

It is a BULL barrel, 22" (same as my sporter was), 11 deg target crown. Heavy as lead! 1:9 twist, rifling looks gorgeous.

Can't wait to get this headspaced and the leade measured / lands and give it a whirl!

docsleepy
May 25, 2013, 07:34 PM
The new barrel is installed. Before I installed it, I re-measured the headspacing of the old barrel and found it easily closed on a go-gauge, and met resistance at the top of the throw if a piece of cellophane tape were added to rear of the go gauge. I installed the new barrel to be as close to the same as possible.

Headspaced so that it closes on a go gauge, meets resistance at top of bolt throw if a piece of cellophane tape (.003) is added to the rear of the go gauge.

Locktited the action screws, firmly tightened (still don't have a FAT).

Verified that the entire barrel is free floated.

Made some measurements with a resized loaded round that suggested the placement of the datum line on the new barrel is within a few thousandths of where it was on the old barrel. In other words, I verified that the bolt would snuggle up to the barrel just about exactly the same as before (chamber appears cut correctly).

Also I compared my sized brass to the Wilson headspace gauge and they fit perfectly in the gauge. The Wilson gauge includes a groove or slot which establishes the minimum case (head to datum) length, and the end of the headspacer gauge establishes the maximum head-to-datum length. There appears to be .006 difference. A randomly selected full sized round was at the minimum distance. The go-gauge was .002" longer. This suggests my brass are perhaps .003-.004" shorter than the (new) headspace available with the newly placed barrel.

I hve to do a case at the hospital at 2AM so this is all for the day and perhaps I'll get to try the barrel either Sunday afternoon or Monday, which is a holiday here.

Andrew Leigh
May 26, 2013, 12:59 AM
Looking good Doc, now with the bull barrel we do not want to see groups but one hole :).

BluegrassDan
May 27, 2013, 12:04 PM
Let's see how it shoots!

docsleepy
May 27, 2013, 05:59 PM
OK, here is the OCW test, first go at it, on the new barrel.

1. Measurements indicated that I might have headspaced the new barrel .001 or so shorter than the last one. As a result, I turned my FL sizing down slightly more into the press to be certain that the brass goes into the chamber without probloems. My rough sighiting in done with brass from last barrel indicated once again that "tight" cases shot low. I have no idea why, now. I now have a Wilson case-headspace tool (sort of a "chamber") and measurements on it from fired cases from the rough sightin allowed me to set the FL sizer to make NEW Hornady .308 match cases' shoulders become just .001 or .002 shorter than fired cases.

2. Hornady OAL measurement indicated the max COAL with 120 grain Sierra spire points is a bit longer than my previous barrel, at 2.880" I temporarily had misplaced the Hornady bullet comparator tool so wasn't able to measure that and had to work with COALs. The COAL to lands with the same bullet in the cheap sporter barrel was about 2.772, over a tenth of an inch shorter.....

3. This longer throat made it much more difficult to load "into the lands" so I decided to load to .040" shorter than the lands, which still had me putting the bullets less than a diameter worth into the necks..... I settled on 2.840" COAL.

4. The new barrel is a 9" twist, 22" long, bull barrel.

5. I took NEW Hornady match .308 cases, lubed, FLsized, then beveled (chamfered), then smoothed with steel wool, then Neck Sized (collet sizer -- this reduces and equalizes the neck tension on all cases; you can tell it is reducing neck tension because the mandrel takes a bit of a push to insert into the freshly FL sized cases), then charged with a RCBS Chargemaster, then bullets seated to 2.842 +/- .002". I have found that you get better results from my Lee seater if you seat, and then re-push the seater. Still, I checked every case and a couple needed a third push.

Charges used were 40.4 (used for sighting and then in the mix also), 40.8, 41.2, 41.6, 42.0 and 42.4 It turned out that I should have made up higher charges.....oh, well, for another day.

The rifle had been cleaned and oiled after the rough sighting in (about 25 shots as a break-in) and I did NOTHING to it prior to shooting. Temperatures ambient 82-85 degrees, I'm shooting from a shaded benchrest.

As usual, all the charges were shot "round-robin" instead of shooting one powder group, then the next etc. About a minute or two between shots, and about 5 minutes to cool between each round. Front rest is RCBS "rock" and rear is a leather bunny. Firm hold applied to gun. Wooden shim around skinny forearm, so it rides well in the RCBS front rest. 16X scope, parallax adjusted out, rifle is easily held within 1/4" of center.

All the "bullseye" circles are 1" diameter. There is also a 1" bar shown in each photo to make it obvious.

RESULTS:
1. The velocities for each shot are marked beside the imprint. There is more dispersion than I had when I annealed my cases, but they were also loaded right next to the lands, and that might have had an impact.
2. First shot was distressingly high, second was lower and then I started the groups. I ignored that for now.
3. The velocities observed are now slighltly LOWER than the Sierra predictions--which makes sense since I have a longer COAL, and a shorter barrel. All my velociites are within safe pressure ranges if their book is correct. I had zero cases difficult to insert, and zero cases difficult to remove.
4. The groups started large and progressively got smaller;p the 42.4 3-shot group is a 45 degree string, all touching; there are three shots; the pink geometric mean marker is covering the center shot.
5. The vertical placement moves slowly up and right, and then jumps up almost an inch with the 41.6 group (velocity about 2820 fps), then inexplicably moves down 1/2 an inch with the 42.0 grain group, belocity about 2875, and then back up to almost the same height as the 41.6 grain group, with the final 42.4 grain group, velocity about 2880.
6. In the confusing final figure, I plotted the geometric centers with "error bars" that are the size of the group extreme spread. Sorry this is excessively confusing.

Looks like it would be good to re-do the top end and extend to 42.8 and 43.2 grains. For another day. Nice group at 42.4!!

docsleepy
May 27, 2013, 06:06 PM
I didn't photograph the first / second shots, but I did record their velocities:

40.4 grains, cold shot, 2935 fps (WAY faster than the 40.4 group average!!)
40.4 grains, 2nd shot, 2809 fps (still faster than the 40.4 group average)

AFter these two shots, I re-adjusted the vertical on the scope to bring the shots 2" lower, turns out I should hve only gone down 1". Should have taken them a bit left, also from the looks of the targets. Oh well. Got it done.

Also picked up another family that probably wants to learn how to reload while I was there today and explained the OCW process to another curious group. I make quite a spectacle with the chrony, notebook, and all the paraphenalia.

docsleepy
May 27, 2013, 06:30 PM
OK, now that I have a "proper" commercial bull barrel on my Savage action, I feel more comfortable about confessing exactly what the "old barrel" was. A photo is attached.

This was an $85 factory sporter 7mm08 barrel that shot fair to poor. I could NOT get it to shoot well enough to make me happy, so I decided to replace it. What to do with the throw-away barrel? No one else would want it, knowing that I had discarded it.... I remembered that some benchrest rifles are made by "sleeving" a Remington 700 action (to make it more STIFF) and I wondered if anyone does that to barrels.

According to an essay on the Lilja (barrel-maker) web site, the stiffness (and thus accuracy) of a barrel increases by the 4th power of the diameter, and decreases by the third power of the length. Short, fat, best accuracy.

Sure enough, there is a company that does just that! http://www.gunsamerica.com/blog/extreme-accuracy-makeover-the-teludyne-tti-tech-straightjacket/ For some few hundreds of $$, I could have a barrel sleeved.... But I of course wasn't going to do that to my throw-away barrel, so I decided to try a "homemade" sleeve..... 3/4" galvanized steel waterpipe, Home Depot, cut to length, inserted until it stops on the slope of the sporter barrel, then very very carefully "poured" warmed JBWeld into the gap a bit at a time and tried hard to avoid any "voids". I have not xrayed it, so I don't know how bad the remaining voids are, but I got it reasonably centered with matchsticks.

It then proceeded to shoot noticeably better groups! Of course, nothing changed about the location of the "lands" or the chamber dimensions. The "first shot" error became PAINFULLY OBVIOUS now that the gun could easily pull off pretty reasonable groups time after time. That is what led to this thread -- I had a barrel that could shoot reasonable groups, but would NOT put the "first shot" near that group, and hence was still a big problem for hunting.... thus my request for advice, that led to all these posts......

So now, we'll soon see if the Shilen commercial barrel, tuned up via the OCW process, can conquer the first shot problem!

ngnrd
May 27, 2013, 08:45 PM
First shot was distressingly high, ... I ignored that for now.

Isn't that what started this thread to begin with?

docsleepy
May 27, 2013, 09:32 PM
ngnrd -- yes! That's exactly why it was "distressing"

The odd thing is that with this barrel (and n=1 tests) the velocity was HIGH rather than low (as with the previous barrel). Note that I had CLEANED the barrel and OILED it after the previous session. Perhaps the oil lubed it well enough to reduce friction enough to increase the velocity significantly. It never did that with the cheap barrel!


I did nothing to the barrel after today's session, stored it dirty. Next time I'm out, I'll simply shoot it, expecting the increased friction to SLOW the velocity. It will be interesting to see where that shot goes, and what the velocity is.

If that doesn't work, then I'll try cleaning it but finishing with several dry patches (leaving no lubrication).

And if THAT doesn't work, then its time to try the grease idea again.

I'll load the cold shots with the optimum charge weight determined by today's tests. Hopefullly, one or the other treatments will work and solve my problem!

If not, then I'll turn again to the great folks on this board for more ideas.....

ngnrd
May 28, 2013, 02:01 PM
Before I got back to working up handloads, I'd shoot some factory ammo through it to see if the barrel swap cured the "first shot high" situation.

ironworkerwill
May 28, 2013, 03:32 PM
Ok, did you true up the action face and recoil lug? The action may not be out by much but the recoil lug (FACTORY) will be several thou smaller at the top compaired to the bottom.

looks nice btw

docsleepy
May 28, 2013, 04:14 PM
Probably a good idea to go get some factory.

Did not true the action. Am using a precision ground Recoil lug and nut. The recoil lug was a precision ground even with the last barrel.

Andrew Leigh
May 29, 2013, 12:58 AM
Just some total fliers here Doc.

Before you take your first shot is your barrel dry. I oil my barrel after cleaning, for storage that is, and then run two tight patches through to remove all the oil before firing and I stay on the money. Is the chamber also dry?

If you are still high with two barrels then how can it be the barrels, especially given that the new barrel is also heavier and more stable?

Do you hold the forearm down when benching?

Is it possible that the bag in your front rest is incorrecly packed and that with successive shots that the media in the bag settles and starts to give good results?

BluegrassDan
May 29, 2013, 08:12 AM
I think Andrew Leigh could be correct. There's something inconsistant with that first shot, and it could be related to the position in the rest. The idea of the bag settling makes good sense. Does the gun return to the exact same position in the rests from shot to shot?

What kind of wooden shim are you putting between the forearm and bag? Seems unnecessary and potentially harmful to accuracy.

Not to be redundant, or to repeat myself, OR keep saying the same thing over and over, but you need to consider getting a dang torque wrench. As anal as you're being about these minute details, your gun could benefit by equal tension on the action screws. And Loc Tite is not necessary on your action screws if you have around 60 inch pounds of pressure on them.

Glad to see the smaller groups.

docsleepy
May 29, 2013, 01:25 PM
You guys are killing me with great ideas!

Okay, so I ordered the F a T wrench from Midway. It will be here soon.

The barrel should not have been wet, it was
Patched with a small amount of oil after the last session, and the rifle in controlled conditions in between. I do think I forgot to swab the chamber, but I did it later and didn't pick up anything.

Frankly, I don't make much of one test, and this is still a very new barrel with less than 45shots through it.

I don't think the front rest packs any at all. The bottom portion of the rest is pretty uniformly packed. This is a hunting rifle, remember? It has swivels on the bottom of the firearm. The wood shim is made of one by fours, in a U-shape, with holes for the swivels. Allows it to fit the front rest. Dramatically reduces cant.

I can't swear that this rifle returns to the exact same position. The rear bag tends to move with each shot. It is possible that I am not starting with the same position in the rear bunny ears. I will take pains to bang the butt down in the bunny ears the next time, Before the first shot.

My hold on hunting rifles for benchrest is a firm grasp on the rifle, I'm pulling it back into the shoulder pocket with about 5 pounds of pressure. I don't make a specific effort to hold the forearm down, more back. The forearm does not really jump. With my extremely heavy six PPC rifle, you can completely let go of the rifle, and touch the trigger, and the rifle will move 2 inches back and stop. Not so this lightweight 7 mm08.

For the next cold shot, I want to try doing nothing to the barrel. Then the following time I will try your suggestion of dry patches after previous cleaning well.

Great ideas, guys! Looks to me like 42.4 or so is going to be the accuracy node. I will try another test around that region.

docsleepy
May 30, 2013, 02:41 PM
OK, so here is the data from the "foulers" this morning 85 deg F.

It was a bright sunny day, so my chronometer never picked up any shot except one time.

Loading: 42.4 grains, the optimum from the previous outing, brass was some of that used in the previous outing, never annealed, new Hornady 308 match brass, necked down to 7mm08 in FL die.

FL sized, neck sized (noted normal pop inserting the mandrel in the neck, felt like normal to slightly high neck tension), charged on Chargemaster, loaded to same length as last time. I loaded seven rounds this same way as foulers/cold shot tests.

Note that I adjusted the windage of the scope to move the POI 4 clicks (1" at 100 yards) to the LEFT. This was because the 42.4 grain load previously shot 1" to the right. No other adjustments.

Tested the fore n aft movement of rifle in bag/front rest, and made SURE to push the butt down into the "ears" of the rear leather rest.

Did absolutely nothing to the barrel except ran a dry patch into the chamber only. It was not cleaned or lubed at the conclusion of the previous session.

As always, the diameter of the circle is 1"

RESULTS:
1. The first three shots are a cloverleaf!! Just about 1/4" higher than predicted by the previous session's results. This is VERY GOOD! I dunno why the 4 clicks ended up with the shots 1/4" too far to the left, but that is no big deal.
2. I next shot the OCW "round robin" tests (see next post). As the barrel was becoming progressively warmer, I shot the shot labeled "warm" which is slightly more leftward and sligtly lower. Near the end of the entire session, I shot the "hot" shot, which was considerably lower.

CONCLUSION:
There is no discernible error in the "cold shot" in this day's tests. Only when the barrel has run >15 shots through it does the point of impact begin to shift. This result is very acceptable for hunting, since I've never shot more than 2 shots. Can't say for sure if it is the rear bag banging, or the lack of cleaning, but whatever, it worked at least today.

WOW! Big improvement! Hope it is repeatable!

docsleepy
May 30, 2013, 03:04 PM
OK, here are the result of testing somewhat higher charge weights.

Look a bit carefully at the photo -- the bullets are landing low and left of the aim point, so you may be confused. On the top row are charges 42.0, 42.4 , 42.8; on the bottom row is the 43.2 and the bottom right group shows the geometric centers of each of the groups (they are clustered very closely together) and the center of the foulers (which is higher, see below for the differences).

CASE PREP
I decided to test my annealing as well while doing this. Absolutely new Hornady .308 match cases were lubed, sized down to 7mm08 in a Lee FL sizing die, outside lube wiped off, and then annealed via my standard procedure described in posts above, dried in 200 degree heat for 20 minutes (and left alone for an hour while I did other things). They were then inside neck lubed and Lee Collet neck sized and primed, then charged using RCBS chargemaster at the various weights, and bullets seated to the same length as the previous session. All lengths were checked within .003" and fixed if necessary.

Things noted:
1. It was very obvious that the neck tension developed by the FL sizer was not as high; the mandrel of the Lee collet went into the cases with notably less effort (still some, but less) than I'm used to with cases that have been used several times. This was quite curious to me. I take it to mean that the brass was indeed softer, and actually softer than I'm used to with multiply sized / annealed cases. Normally when you collet neck size these cases, you have the distinct feeling of the mandrel forcing itself into the FL-sized neck (Lee must set their collet mandrel slightly greater diameter than their expander ball in the FL die....) and also when you withdraw the case from the die, there is a distinct pop (like children make with their finger popping out of their cheek/mouth) due to the suction developed as the tight neck comes down the mandrel. I didn't get as much of that "suction sound" as I'm used to.

So my take on this was that these necks (annealed when not hardened except by the FL neck sizing reduction from perhaps .306 to .282 or so) were SOFTER than my usual experience.

2. When I inserted the bullets, it was also plainly evident by feel that they slid in with much less force than I'm used to -- the foulers went in with a notable initial resistance as the bullet forced its way into the neck.

So I concluded that I had a set of brass with an unusually soft set of necks --even for me. How would they shoot?

RESULTS:

1. Again the groups at 42.0 and 42.4 are the best -- but they are not as good as the un-annealed brass results of the previous session, and clearly not as good even as the three "cold-shot-foulers" !
2. The VERTICAL movement of the groups -- the primary purpose of all this optimal charge weight testing -- demonstrated that all these charge weights today are virtually identical. The geometric means moves almost none at all,while the group size blows up above 42.4 grains.
3. The last (hottest barrel) shot at the highest powder level is actually higher than expected. I think the group is just widening, but this was interesting.

CONCLUSIONS:
1. 42.4 (at 85 degrees F) seems to be the optimal charge; at this point the vertical position is fairly fixed, and the group size is minimized.
2. I was NOT able to get any velocities due to lack of clouds, so can't measure velocity standard deviations.
3. This neck tension seems BELOW the optimal range -- too soft brass. Andrew and the others will be glad to see this proof! Apparently the working of the brass with initial necking down is not that much, and it would be better to go a few shots/reloadings before any annealing (I know they will agree). The overly soft necks seem to have resulted in larger groups. And a lower, and leftward point of impact. The POI change could be adjusted for, but the group size is suboptimal. There was a note in the "warehouse studies" article posted above that they noted that any bullets that seated with a required force below a certain point, shot poorly. Seems the same here.

So I may run these brass up and down in the FL die a few times to harden their necks some and compare again??

BluegrassDan
May 31, 2013, 07:55 AM
I think you've figured it out. The POI on lighter weight hunting rifles can shift depending on how the gun is held and/or cradled in the rests. Perhaps your first shots have been high (until now) because the gun was not seated as firmly in the bags as after a few shots.

This is also why the POI of your cloverleaf was 1/4" off from the previous shooting session. You can't duplicate the environment from day to day, and you can only try your best to seat the rifle in the rest, weld your cheek, control your hand positions, and breathe consistently.

I'd quit screwing with annealing the brass. It's overkill, and you're less likely to be consistent. If your best groups were from a cold bore with un-annealled Hornady brass, then use that for a while and see how consistant you can be.

As folks have said before, you've got to "let it ride" for a while. Stick with one thing and practice consistency.

Here's what I suggest. Prep 25 cases of un-annealled Hornady (fire formed and neck sized only WITHOUT lube on the neck - which can create inconsistant neck tension). Load up 5 rounds of 42.0, 5 of 42.1, 5 of 42.2, 5 of 42.3, and 5 of 42.4. Take a few hours at the range (no caffine beforehand), and shoot those 5 shot groups allowing the barrel to cool for 3-5 minutes between shots, and 15-20 minutes between groups. Make sure the gun is seated firmly in those bags before you start, and get rid of that dang wooden shim between your forearm and bag. That's sure to mess things up.

Then do this ENTIRE process again to figure out which load your rifle likes best.

Then come back and tell us which load is best. Simplify, simplify!

docsleepy
May 31, 2013, 05:43 PM
Bluegrassdan: yep, I think you are right. The rear bag may have made a bunch of difference! Pounding it in.

But it bothers me the difference in the point of impact of the (over)annealed cases, and their increased group size. So I set about to find some way to MEASURE my neck tension/annealing:

First, I could NOT find my spring scale so I had to take advantage of Hookes law, and make one first, and calibrate it using a 7 lb weight and assume linearity in the expansion of the automotive spring from PepBoys that I used as the scale device.

Next, I took 2 of the non-annealed cases that shot the excellent cold bore group, and 3 of the over-annealed cases, and proceeded to measure, on a Lee press, at right angles to the arm, with the scale connected by a non-expanding string, to just near the end of the lever arm (using the ball to stop the string). The lever arm is about 18 inches. I measured the force in pounds needed to (1) insert the collet die mandrel in a freshly full-length sized case, and (2) to get the bullet seated -- it just pops in once it starts, because these are flat base bullets.

Here are the results:
[It is difficult to get this thing to space out columns....]
.............................Pounds to..................Pounds to
.............................insert mandrel.............seat bullet
Non-annealed #1..........5#............................6#
Non-annealed #2..........6..............................3

Overannealed #1..........2..............................3
Overannealed #2..........3..............................4
Overannealed #3..........2..............................2


Comment: the overannealed cases a much softer to admit the mandrel after full length sizing, and generally have low forces required to seat the bullet, in agreement with my intuitive sense after loading 16 of them for the last test.

Next, I decided to find out HOW MUCH I was work-hardening the overannealed cases by repetitively full-length sizing them x 3 ( a practice y'all collectively didn't like )

I took Overanneled Case #3 and successively FL sized it and measured the necksizing pressure, until I hit 50 FL sizings: here are the data

Overannealed Case #3
Number of times total FL sized.........Pounds to insert collet die mandrel
6 total.........................................3#
12 total.......................................3#
25 total........................................2#
50 total........................................still about 2#...something makes no sense!

I concluded this wasn't going anywhere, and worked on "bullet seating" force.-- probably more important anyway!

Final experiment:
I took Overannealed Case #1 (which had seated with 3 lbs force) and FL sized it five times and then neck sized it ( measured 5 pounds!!!) and then seated a bullet -- SIX POUNDS. Same as Non-annealed case #1!

My conclusion #1 is that something was screwy with my testing technique for overannealed case #3 and the mandrel, and the final test seems to say that you can overanneal a case and with roughly 5 or fewer FL sizings (which sizes the neck both down and up and thus work hardens it) you can return it to the same approximate neck tension as a case that was not annealed since the factory and loaded/shot twice.

Conclusion #2 is that it is possible with simple equipment to measure the bullet seating force and it would probably be smart of me group cases together that have similar necksizing / bullet seating forces -- they are more likely to group siimiliarly. Any case that seats with unusually LOW pressure is likely to shoot LOW in this gun at 85deg Fahrenheit anyway....

#3 And I hope I find my real spring scale soon.

docsleepy
May 31, 2013, 06:26 PM
It next occurred to me to wonder what would be the bullet seating force if I skipped the collet neck sizing die.

So I repeated the test with a fresh twice-loaded/shot non-annealed new case: bullet seating force after only FL sizing approx 7.5 lbs.

Overannealed case, shot once since annealing: bullet seating force after only FL sizing -- approx 6 lbs. Still lower than the non-annealed, but not unreasonable.

The lee neck collet mandrel must be a bit smaller in dia. than the expander ball in their FL 7mm08 sizing die.

docsleepy
June 1, 2013, 01:15 PM
As one person requested, I purchased some commercial 120 grain 7 mm 08 ammunition.

I think I will use a kinetic bullet puller to remove one bullet, resize, and measure the bullet insertion force on the commercial ammunition. That will give me a baseline for what hardness the commercial guys think is optimum.

John C
June 1, 2013, 09:33 PM
As you mentioned, it sounds like you're over-annealing your brass, softening it too much.

Here's an affordable machine that makes the guess work out of annealing: http://www.cartridgeanneal.com/

Check it out.

-John

docsleepy
June 1, 2013, 10:42 PM
Very impressive. I watched the video. He's using more heat than I use but way less time. Think this is worth trying.

John C
June 2, 2013, 12:32 AM
Doc;

That's what I suspected. There are some good articles on the technical aspects of annealing cartridge brass. Basically, there is steep arcing curve as to heat and time and what that does to the brass. Too long under the heat, or too much total heat, no good. Too little heat, for not enough time; also no good.

A lot of bench rest shooters anneal after every firing, but they're annealing under very controlled, repeatable conditions.

I want to say that I've enjoyed this thread immensely, along with your Mosin thread. I've enjoyed seeing you wring out your process for repeatability. I also appreciate your desire for bang for the buck, but also your willingness to spend money for results. This thread has turned out to be a great primer on how to accurize a Savage. I just bought a Savage 110 from 1989, and I'd like to follow in your footsteps.

I think that once you sort out your annealing process, either by giving up on it or getting a repeatable process, and a getting a torque wrench, you'll be mostly there.

Does this rifle have an accu-trigger? Whether it does or not, have you tuned the trigger down to the lowest possible weight? Even if you don't want too low of a trigger weight for hunting, while you're dialling in you rifle, you may want to lower the trigger weight, and then raise it for hunting. With an accu-trigger, the safety issues of a low trigger weight are largely obviated.

-John

docsleepy
June 2, 2013, 07:21 AM
Great comments! I ordered a bottle of the Tempilaq

remember I had been FL sizing three times after annealing, and I guess I had blundered into a way to return to a normal hardness. We'll see. video suggested that all I was still way over annealing and if this will make it more repeatable, I'm all for it! I started annealing when I had the opposite problem, way too hard brass, and bullets would simply fall out. At that time, one annealing gave me some of the best groups I had had for a while. However, my process doesn't seem perfect, at all

This neck tension thing seems key. I ordered a Wilson
Inline seater, on clearance! From Midway last night. I can put it on top of a bathroom scale, and then seat by hand, or Arbor press I have an arbor press. The scale will allow me to measure seating pressures, giving me a way to sort my loaded cases.

From the results above, the difference between normal hardness and over annealed was about an inch at 100 yards. So it should be easy to tighten the process so that I consistently achieve less than half an inch. That will be plenty adequate.

This savage is an old one, and does not have an Accu
trigger. I have the trigger adjusted pretty light, in the range of 2 pounds. Once the screw got loose, and it went down to 1 pound and became erratic! I drilled a small hole in the stock so I can reach the adjustment screw without having to take it apart.

This has been great, getting all these wonderful comments and suggestions from everyone! When I have my neck seating pressure sorted out, I put some more data up.

John C
June 2, 2013, 11:44 AM
Keep in mind you may need a second torch, or a method to reliably spin the case so that you uniformly heat the case neck.

Without a high end annealing machine, I think the two torch method would be best. I actually think the Anneal Rite machine looks pretty cost effective. I'm considering getting one. If I like the result, I can upgrade to a $400 machine.

-John

docsleepy
June 2, 2013, 12:34 PM
Yes it looks very nice. I may build it or buy. Easy to add second torch.

docsleepy
June 9, 2013, 08:23 AM
Been busy with some other projects. Finally got back to this one.

Goal: compare seating forces between
a) new out of the box Hornady .308 match cases FL sized to 7mm08
b) used many times, annealed many times, annealed, shot, resized; initial and after successive resizings
c) lightly annealed new Hornady .308 match cases FL sized to 7mm08 (2 cases)
d) overannealed new Hornady .308 match cases FL sized to 7mm08, initially and after additional successive resizings (2 cases)
e) A commercial loaded round disassembled and tested.

I attempted to use a bathroom weight scale, the Wilson 7mm08 inline seating die, and an arbor press to measure seating pressures. Getting the stuff inside the gap of the arbor press was problematic. Using my weight directly on the inline seater, I reached 120 lbs. and STILL could not seat a bullet.....I gave up and went back to using the homemade spring strain gage at right angles to the Lee handle, crudely calibrated. (See photo)

Group B was one of my many-times used cases that shot low in a recent test. I re-annealed it to maroon, tested, then resized/re-colleted, measured seating force, and repeated (3 total sizings and measurements)

Group C was annealed to maroon and tested.

Group D was intentionally "over-annealed" past "maroon" to definite RED (but not orange) color. This is how I might have annealed cases when unsure of whether I'd seen the color change. You'll see these results are DEFINITE

Group E was a Fusion 120-grain commercial loaded round, with a cannelure, kinetic disassembled, deprimed, lubed, sized, chamfered, collet sized (my standard procedure at every point), and then bullet seating pressure measured.


======================================================
RESULTS -- APPROXIMATE SEATING PRESSURE FOR FLAT BASE SIERRA 120GRAIN SPIRE POINT BULLET AT END OF HANDLE OF LEEE PRESS

Group......................A.........B.........C.............D..........E
..........................NEW......TYPICAL.ANNEAL...OVER,,,,,,COMMERCIAL
..........................CASE.....ANNEAL..NEW.......ANNEAL...ROUND
TEST #
Initial....................5#........3#........5#,5#......1#,2#.....2#
2nd......................X..........4-5#.......X...........3#,4#.....X
3rd.......................X..........5#..........X..........4#,6#.....X

X means test not done
=====================================================


My Conclusions:
1. The commercial round appears to be softer than I would expect, maybe that is because they are using cannelured bullets and likely crimping.
2. ANNEALED TO RED CASES ARE DEFINITELY SOFTER AND AS SHOWN BEFORE, SHOOT LOW IN MY GUN! Re-sizing them multiple times appears to bring them back to reasonable hardness -- big result!! -- at least three times needed in my test.
3. Annealed new cases to just barely color (maroon) appears to have minimal effect; annealiing multiply used cases gave an intermediate effect (3#) -- probably shows inconsistency in either brass, or more likely, mytecnique. Re-sizing one more time returned those cases to the range of "normal".

P.S. My TempiLaq has arrived. Another opportunity to learn!

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