Help me tighten my groups...


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Afy
September 14, 2008, 12:58 PM
Ok this is the result from todays shooting @ 100 meters.
http://i256.photobucket.com/albums/hh178/afy08/IMGP0331.jpg

Now for each of these loads, excluding factory... how much higher and lower do I test. I worked these up using OBT and Quickload, and in the case of the 139 Scenar heresay...

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rodregier
September 14, 2008, 01:22 PM
The 123 Scenar @ 38.79 N-150 looks good enough for now. Make more of those and get some practice time in.

Strongbad
September 14, 2008, 02:24 PM
Agreed, that's pretty darn good shooting. Depending on how long between shots, try giving more time to cool between shots and see how temp sensitive the gun is.

Refine your bench technique, the hold, your breathing, etc. to make sure that it's absolutely perfect.

Tweak the loads... a little more powder, a little less powder. Move the bullet out, move the bullet in, that kind of thing. Only problem is you get down to the hair splitting phase quick! :)

Finally, tune the gun. Bedding & trigger, that kind of thing.

Afy
September 14, 2008, 02:56 PM
Its an average of about 1 shot every 30 seconds, and about 5 minutes between groups.

The trigger is an Accutrigger, that breaks very cleanly and lightly.
Gun is on an aluminum HS Precision Stock... not much to tune. Barrel is a Walther 27.5 inch 1 in 8.
At al OAL of 2.864 its about .02 off the lands.
I am going to be playing with powder and bullet weights 107-140 gr. :)

SlamFire1
September 14, 2008, 04:47 PM
Very good shooting.

Hard to improve on sub MOA shooting.

MarshallDodge
September 14, 2008, 04:53 PM
Are you shooting off a rest or bipod?

Those look like my groups when I shoot off of a bipod. When I shoot from a sandbag rest they tighten up quite a bit.

JFettig
September 14, 2008, 05:44 PM
Move out to 200 yards and see what you can do. I can shoot better MOA at 200 than 100(me, not the rifle or ammo).

If your shooting from a deadsled and know its the rifle/ammo thats shooting that, you could measure the max OAL and find the optimum jump if any, try lighter loads, hotter loads, lighter bullets, etc. Therse just too many things that you can do. You could go as far as uniforming primer pockets, neck sizing, flash hole uniforming, weighing each case and sorting by weight, etc.

Jon

Walkalong
September 14, 2008, 07:52 PM
Pretty good shooting. Very good really, but if you want to improve.

Try different O.A.L.'s to see if your rifle has a liking for one. I would try .020 into the lands first if it was me, then just at the lands, then .020 jump to the lands. Your rifle may have a distinct liking for one of them.

You don't give a load, but I would tweak it up and down after I found the seating depth my rifle liked.

Order of importance

Bullet - Find one your barrel likes

Seating Depth - Find one that bullet and your barrel likes

Powder & Powder Charge - Find one that combo likes

Primer - Sometimes they make a difference

Basically. :)

Oh, and if you want to shoot better than that consistently, get some wind flags and learn how to use them. ;)

dwave
September 14, 2008, 08:15 PM
Primer - Sometimes they make a difference

Huge difference sometimes. I had worked up a load for my .303 using Varget with CCI primers. My local "shop" ran out of CCIs so I got federals instead and just used my regular powder charge (only .2 over the min.) and the group sizes doubled! Rifle hated that primer/powder charge combo. SO, moral of this story? Consistency! Stay consistent with the components when working up a load. Same primers, brass trimmed the same, ect. Only change one thing at a time, and if the gun gets better, then go with it, gets worse, ditch it and go back.

280shooter
September 14, 2008, 11:15 PM
Stay with one brand of brass,one brand of primmers too.check your oal.
Maybe you can try using your scale for each powder charge,
Is your scope mounts tight,trigger weight? let your gun cool down between shots,did you clean your bore,Maybe your gun like boattails, maybe it does better with flat base,Only change one thing at a time,and small changes,are the best,

rapier5316
September 14, 2008, 11:43 PM
Are the cases of a length and the mouths clean and square?

What sort of runout figures are you getting?

I am new here, but I have found your thread on the .260. I thought you were dealing with a 6.5 by the bullet weights mentioned.

Is the 3-9X scope still on it? Personally, my groups shrank with a target/tactical/varmint style scope and reticle. An interim trick is to use the cross hairs as a border on the aiming point. That is to nestle the aiming point in the crotch of the intersection of the cross.

Bullet
September 15, 2008, 12:56 AM
Copied from another forum -

There are some pretty universal rules about seating a bullet. You first seat the bullet to a given depth and then work up with the charge. To do otherwise might lead to a pressure excursion. Do you know how to read pressure in a rifle case??? If the radius of the primer is gone,the bolt lifts hard,you can see the extrusion of brass back into the elector hole,see the machine marks on the bolt face in the brass or the primer flat falls out of the case the load may be a bit hot. BUT, this can and will happen regardless of where the bullet is seated if you tip the powder bottle too much. Here's a very easy way to develope a load:
1)-Set the bullet into the lands(if you can reach them) as much as the neck tension of the case will allow.
2)-Start with a minimum listed powder charge or -10% for the bullet weight
3)-Work the powder charge up till the groups get as small as they will get.
This depends on the rifle.
4)-After getting as small a group as the rifle will shoot at the jam,back the bullet off.002/.003 at a time and see if the groups improve.Depending on the rifle they may or may not.
5)-If you decide on trying another bullet back the powder down and go back to the jam length and start again.
What this saves is guesswork. If the bullet is seated HARD into the lands then the only way to go with it is shorter. If the bullet is seated HARD into the lands and you have a safe working load pressures will NOT increase as the seating depth is shortened. If you, at any point,. get pressure signs, STOP. Back off the powder and start up again and see if it repeats. Be aware that a load shot at 70 degreesF. may not be a safe load at 100 degrees F.Back a load off when you change ANY part of that load including changing lots of the same brand of powder. Never assume anything;prove it to yourself. There is not really a lot of rocket science in rifles; experience is much more important

Since you have Quickload I’d recommend starting with one bullet weight. The heaviest one you want to try. See what the MAX load is for this bullet using the powder you want to try. Then reduce the powder charge from MAX by 10% and load 5 cartridges at the lower powder charge (starting load) and continue to load 5 cartridges each at .5 grain increments until you reach the MAX load or see any signs of pressure. Once you’ve shot these , see which powder charge shoots the best and then go back to it and load .2 grains above and below and shoot again to see any improvement. Once the power charge that shoots the best has been found then try different seating depths to see if you get any improvement. I’ve found that the type/brand of powder can make a big difference in group size when using match grade bullets.

With your new rifle I believe you should see groups less than Ĺ inch at 100 yards (heck my AR will shoot under Ĺ inch at 100).

Afy
September 15, 2008, 06:32 AM
Rapier: All cases are the same length, and squared away.

I do not own a concentricity guage, so couldnt tell you about run out. However rolling the cartridge ... my guess would be nil.
3-9x is broken. So replaced with a Weaver 4.5-14x40 from my .300 WM until my Leupold 6.5x20 catches up with me. Might even switch to a Nightforce NF 12-42x56 not sure yet.

Bullet: Am working up loads now. Will also try to get out to 200 and 300 meters and see what happens.

Have also ordered an HM Precision Rest.

Bullet
September 15, 2008, 09:07 AM
Bullet: Am working up loads now. Will also try to get out to 200 and 300 meters and see what happens.

In general longer distances will increase group MOA size. My experience is with more distance you get more effects from the wind, Doesnít help for shooting little groups.

Quigley
September 15, 2008, 10:13 AM
If you are using a bipod, sandbag up a good shooting base and try turning the magnification down on your scope. 6x or less...

243winxb
September 15, 2008, 10:31 AM
http://findarticles.com/p/articles/mi_m0BQY/is_4_48/ai_83483904 Great info at this link. Case prep will help most now. Redding full length sizing type S Bushing dies can be used with or without the expander for brass that is unturned or turned. Send 3 fired factory cases from your gun for custom fitting (if the still do that?). Size 1/2 of the neck. Outside neck turning. Uniform flash holes first* then weight and sort NEW UNFIRED brass. competition bullet seating die. 36 power scope or other high power variable. 36 power is almost useless when trying to shoot in conditions with mirage and heat waves, unless your an expert at reading conditions. Wind flags are a must have.

Afy
September 15, 2008, 01:47 PM
I dont think I am going to go down the route of super prepping the cases at this stage. I already use the Redding dies and am looking around for affoardable Type S competition dies. Alternatively the Forrester Seating die.
Am still looking for better loads... so am going to go +/- 10 % in .2 gr increments and do the ladder to see what can be eeked out, before going into the super case prep stage.

In all honesty I rarely get a chance to shoot beyond 300 meters. Maybe a couple of times a year. Not many places to do that around Europe that are easily accessable.

NCsmitty
September 15, 2008, 04:39 PM
Am still looking for better loads... so am going to go +/- 10 % in .2 gr increments and do the ladder to see what can be eeked out, before going into the super case prep stage.
I think that this route is the common sense approach to your fine tuning. The super case prep may give you a tiny edge but requires a lot of time and dedication and IMO, is not the option that you need right now. Load workup and some more break-in time on the barrel will give you the greatest bang for your time invested.

NCsmitty

Strongbad
September 15, 2008, 06:08 PM
Gun is on an aluminum HS Precision Stock... not much to tune

Don't count on it. You may be a step ahead of a wood stock, but remember that the HS stocks come off of an assembly line just like anything else and may be sloppy from time to time. The one on my Mark V Weatherby was and had to be bedded and that's not the only one I've seen like that. Not saying that it'll help one way or the other in your case, just keep it in mind. :)

Eric F
September 15, 2008, 06:23 PM
Hey folks your missing the most important thing in getting tighter groups..................GET CLOSER TO THE TARGET!!!:neener:

Bullet
September 15, 2008, 07:37 PM
Quigley
If you are using a bipod, sandbag up a good shooting base and try turning the magnification down on your scope. 6x or less...


Why do you recommend 6x or less?


.

tbtrout
September 15, 2008, 08:52 PM
I would leave the load alone and work on breathing and trigger control.


Good shooting

cliffy
September 15, 2008, 09:15 PM
I'm now spoiled at 20x, with 24x to go. Seeing is incredible: holding is another story. How could I miss the entire target on the second shot? After walking up to the target, I saw I didn't actually miss. 6x is great at 50 yards off-hand, but 100 yards off a bench loves a 20x scope. My eyes have incredibly improved since my cataract surgery, but I take nothing for granted. 12x is excellent for 100 yard shooting, but 16x is better, as apparently is 20x. Tomorrow, is range day again after the aftermath of IKE, the rainmaker. My back yard may be underwater, but I hope the range is walkable without hipboots. I can barely see the 3" target at 4x, but my eyes are better than ever. cliffy

Walkalong
September 15, 2008, 10:05 PM
High magnification is hard to use offhand, but you can't beat it from a rest for shooting tight groups.

Bullet
September 15, 2008, 10:41 PM
High magnification is hard to use offhand, but you can't beat it from a rest for shooting tight groups.

On my 2 best shooting rifles, one has a 6x18 scope the other is a 6.5x20. I think my next scope will be a fixed power 35 or 40. The X in F-class targets are hard to see.

rapier5316
September 15, 2008, 10:45 PM
http://img292.imageshack.us/img292/6627/valkyriefliesfullcase002wp7.jpg (http://imageshack.us)

Less than .002 runout, over 004 opens to .75 inch groups at 100 yards

http://img405.imageshack.us/img405/5692/valkyriewithleupold005ba0.jpg (http://imageshack.us)

Afy
September 16, 2008, 06:14 AM
Rapier not sure I understand. Could you elaborate please.

rapier5316
September 16, 2008, 05:27 PM
Those 2 groups were fired with rounds that were measured at less than .oo2 runout. When the runout of the rounds were .004 or greater the groups opened up to .75 inchs.

You are already shooting under MOA. Shrinking the 100 yard groups now becomes a matter of construction, developing shooting technique, ?

Most can eliminate the pesky flier by sorting their rounds and shooting scores with only the very straightest of bullet sets.

THis is also a fairly economic course of action. The RCBS case master can be had for under 90usd. Even the roller bearing Sinclair Int'l unit is under 100usd.

The rest of the equation here is: .22-284 using Lapua 6.5-284 brass sized to 224. Nosler 80 grain hp Match bullet. Federal large rifle magnum match primer using a 50 bmg powder. Firing in a 3 groove Lilja 1 in 8 twist with a finish length of 29 inchs plus the 1 9/16 inch brake.

You'll like the Leupold. Only 10 moa adjustment short of the Night Force for 4-500 usd less money.

Afy
September 17, 2008, 04:37 AM
Am biting the bullet and getting the sinclair...

Now comes the question on setting the run out... how does one do that?
Am also getting the Competition seating dies. Cant decide between Forrestor and Redding.

243winxb
September 17, 2008, 06:42 AM
A rifle chamber has a given volume, this runs from the bolt face to the place where the bullet seals the bore. Any time you change the weight/mass of the loaded round entering this volume, the pressures and velocity changes. The second most important is getting the loaded round centered with the bore. The best way to do (standard chamber, not tight neck)this is full length resizing using a bushing die,(Redding type S) while only sizing half of the neck area and controling the shoulder bump by pushing the shoulder back a mimimum of .002" The outside neck turning must be done to get the neck wall thickness exactly the same so it can center the round in the chamber. Neck sizing only in most cases does not work because 99% of the time the chamber is not in perfect alignment with the bore. Each time you fire the case it get larger in diameters, this changes pressures each time the case is fired, soon it will not chamber at all and will need full length resizing or as some call it, bump the shoulder back. Maybe if you put an index mark on each case and placed the case into the chamber the same as it exited the chamber each time this would not matter,maybe? 2 other ways to center the round in the chamber are 1. bullet jam, but as the gun gets dirty the jam changes. 2. Tight neck chambers used with custom dies. If you want to change your 3/4" average rifle into a 1/4" , case prep must be done IMO.http://findarticles.com/p/articles/mi_m0BQY/is_4_48/ai_83483904

243winxb
September 17, 2008, 07:25 AM
Now comes the question on setting the run out... how does one do that?
Your case prep. The sizing dies used and how the bullet is seated. Bench rest neck sizing dies run in a sleeve, this sleeve needs clearance to function, maybe it does not matter, but a bushing die that flrs at the same time keeps the brass held in a fixed position so the bushing can do its best work, much like a custom die.

Afy
September 17, 2008, 07:27 AM
So what do I need to get... am somewhat of a newbie at this stuff...
Much appreciated.

243winxb
September 17, 2008, 07:37 AM
http://www.redding-reloading.com/pages/typesbushseatdie.html Redding Full Length Resizing Die Type-S Bushing die.Can be use with or without an expander. With 1 bushing to start. An outside neck turner. A flash hole uniformer tool. Bullet seating i use a standard RCBS die, but a custom one might give better results. Your target will let you know if a different seating die is needed. I would hold off on the runout tool for now.

Bullet
September 17, 2008, 09:43 AM
I shoot 308 in a standard size chamber. I use Lapua brass and donít turn the necks. I partially neck size with a Redding neck bushing die with the expander removed. I donít size the body unless my brass becomes hard to chamber. I use a Redding seating die (the one with a micrometer). I get ľ inch groups @ 100 yards. I donít worry about runout since I canít change it.

rapier5316
September 17, 2008, 11:28 AM
Changing runout isn't really the point. Sorting the finished rounds by whatever degree of .oo you want is.

Bullet is using some good practices and is getting good results.

An interesting site is www.6mmbr.com

243winxb
September 17, 2008, 01:19 PM
Any bushing die is far better than standard dies. NO EXPANDER, with or without neck turning. After measuring RCBS standard dies in 223,243, 30-06, i find that the neck is sized down .010" +. Way more than need. Then the expander ball opens the inside of the neck to the correct diameter. This overworking of the brass is where runout can happen. Problems with bushing dies and runout can happen also if the fired case neck(from a large chamber) has to be size down more that.008" to .010" http://www.redding-reloading.com/techlinepages/concentricity_bushdies.htm

243winxb
September 17, 2008, 01:38 PM
http://www.redding-reloading.com/techlinepages/techline.html Redding tips is saying outside neck turning will not improve Concentricity /accuracy with factory chambers> (oversided maybe:confused:) I guess looking at your fired target is the only way to know. OOPS see update at the bottom, they were talking about standard dies, not bushing dies.

Afy
September 17, 2008, 01:44 PM
I have ordered the Redding seating die with micrometer and the Type S Bushing die.

What size bushing would I need? I am using Remington brass currently in .260 and have a standard chamber.

243winxb
September 17, 2008, 01:56 PM
What size bushing would I need? I am using Remington brass currently in .260 and have a standard chamber. Measure the neck diameter of 5 loaded rounds with a micrometer to get an average. The bushing i would buy would be .003" smaller then your average neck diameter. This should get your started with unturned necks. If you deside to outside neck turn, you may need a smaller bushing. You will end up buying at least 3 bushing.

Walkalong
September 17, 2008, 04:29 PM
You will end up buying at least 3 bushing.Most likely. ;)

Bullet
September 17, 2008, 11:49 PM
It has come to our attention through customer calls and our own use of the bushing style sizing dies that in certain instances, a given neck sizing bushing will produce a case neck diameter that can be several thousandths of an inch smaller than the actual diameter of the bushing. This idiosyncrasy occurs when the neck diameter of the fired case is a great deal larger than the diameter of the neck sizing bushing, such as occurs when factory chambers are on the large side of the tolerance range and the brass is on the thin side. Typically, we have not noticed any problems until the case neck is reduced more than 0.008-0.010".

Solutions include, increasing bushing diameter to compensate and/or the use of a size button. Reducing the neck diameter in two smaller steps by using an intermediate diameter bushing will also help. More concentric necks will also result using this method, as the case necks are stressed less during sizing. Don't forget to properly chamfer the inside and outside of the case mouths and apply a light coating of lubricant to the case necks before sizing.

The above was copied from here -

http://www.redding-reloading.com/techlinepages/bushingselection.htm

When I partially resize the necks of my cases I use 2 bushings to reduce the neck diameter in two smaller steps by using an intermediate diameter bushing. I’m not sure if this is necessary but looks like Redding recommends it. I have a tool that measures case concentricity. Haven’t used it for awhile. Think I’ll try Sorting the finished rounds by whatever degree of .oo you want. Like rapier5316 suggests sometime and see if I get any improvement. Some people weigh bullets and cases and sort by bearing length, point the meplats and trim the meplats. I’m not sure how much some of this matters. I would think it would take a very good rifle and shooter to see the differences. But as an old benchrest shooter once told me - you might not see a difference between one thing but when you add them up it makes a difference. I’m pretty happy with my loads but trying to improve groups can be fun.

rapier5316 -
.22-284 using Lapua 6.5-284 brass sized to 224. Nosler 80 grain hp Match bullet.

What bullet speeds are you getting?

Afy
September 18, 2008, 03:27 AM
Bullet: No idea about velocities. Dont have a chrono right now. However the Quickload stuff predicts around 2800 fps with the 123 and 129 Scenar loads.
I am fairly new at the precision stuff... and had until now been mostly a plinker.

243winxb
September 19, 2008, 07:36 AM
http://www.redding-reloading.com/techlinepages/techline.html Titanium bushings need a light coating of lubricant to the case necks before sizing. A single shot rifle can use a bushing that is .001" smaller then the loaded rounds average case neck diameter when OUTSIDE NECK TURNING. A repeating rifle that will feed from a magazine may need a smaller bushing so you don't get bullet set back. Always check you bullet tension, if you can push the bullet into the case with you finger its to light. The expander is NOT used with neck turned brass. Brass that has NOT been NECK TURNED may need the expander used with flat based bullets if your sizing the neck as much as .003" A boatail bullet most times will Not need the expander. You have to make this determination by how much pressure/resistance you feel when seating the bullet. Aways use a nylon brush to clean the inside of the neck. No lube for turned brass. You MUST lube if using the expander. Use a Q-tip to wipe the lube out of the inside of the case neck after sizing.

Afy
September 19, 2008, 07:50 AM
All great info....

It just seems to keep on getting more and more complex. But hey.. if it gets me down to a single hole... I am not complaining. :)

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