How to load for accuracy?


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esheato
February 24, 2005, 05:16 AM
On my sorted (by headstamp and weight), fireformed, clean brass I uniform primer pockets, debur flash holes, trim and chamfer. I use Federal Match primers and use a digital powder dispenser charging cases to the tenth of the grain. I also use Redding Type S Neck Sizing Match Dies seating bullets to an exact and identical measurement. I know this because I use a caliper and comparator on each and every one of them.

...and I'm still only getting consistent .400-.550" center-to-center groups at 100 yards. My goal is to be able to shoot a consistent .200" CTC.

What else needs to be done? What else should I be doing? I'm finally giving in the towel in regards to H322 and working on Benchmark. By the way, I'm shooting a .223 AI with 50 grain Sierra BlitzKings.

Thanks in advance.

Ed

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Wildalaska
February 24, 2005, 05:27 AM
Bullets.......change bullets

WildmatchkingAlaska

dakotasin
February 24, 2005, 10:35 AM
check your runout at both the neck and the bullet ogive. neck wall thickness, too.

you don't mention the barrel... is it a punched out factory tube, or is it a custom? that alone makes a world of difference. trigger? scope? action work? stock?

agree on the bullets. matchkings are about as 'low end' as you can get away w/, and even then you'll probably come up short.

br shooters get consistent .200 ctc, and they have lots invested into a rifle - so don't be too discouraged by not being able to hit that mark... w/ a custom br rig, you'll get those kinds of groups w/o the extreme hassle of nitpicking your loads.

cola8d8
February 24, 2005, 12:03 PM
Have you tried different seating depths? There is a little accuracy to be found there also.

Art Eatman
February 24, 2005, 12:05 PM
dakotasin certainly has some good questions to for you to think about.

And trying different bullets helps. Some rifles are just finicky. I have a .243 that is a sweetheart with lighter bullets, but with a 100-grain Nosler I might as well fling a handful of gravel.

If Sierra still makes their 52-grain HPBT, I found that to be really good in a .220 Swift--but that was 30 years ago. :) But I got five-shot, 3/8" groups and ten-shot 1/2" groups out of a heavy barrel, box-stock Ruger.

Art

Dave P
February 24, 2005, 12:52 PM
Bullets. Maybe sierra 69 bthp? Maybe some berger flat base?

Also try rl-15 if have some handy.

LeonCarr
February 24, 2005, 02:03 PM
If you are looking to shrink groups further than .400, you might try a handmade benchrest type bullet (Berger, etc), turning case necks to a uniform wall thickness, and using Wilson type hand dies for loading. You are doing pretty much everything else :).

Just my .02,
LeonCarr

swifter
February 24, 2005, 02:51 PM
Are you using an aftermarket barrel or a rechambered factory pipe? If the latter, your goal may be unrealistic. :banghead:
You're doing everything right, as far as I can tell. In your shoes, I'd drop the charge 5%, and seat with the bullet 0.005" back from "jam length", then start groups at 0.005" further back, progressively. Once you find the seating depth it likes,then start increasing the charge. Definitely switch to a match bullet, Berger has a good selection.

Get some sort of wind flag set-up, even an old ski pole with a yard of surveyor's tape attached will help. One near your bench, one at 50 yd., one at 75 yd. will tell you a lot about how the wind behaves. The wind willmove your bullet, and it is near impossible to shoot really good groups without being able to read the wind.

Figure in a bench match, any one rifle on the line could shoot well enough to win... The shooters rifle-handling skills are also approximately equal. most of the time, the winner will be the guy who read the conditions the best. :what:

good luck, enjoy! :D

Tom

esheato
February 24, 2005, 05:16 PM
check your runout at both the neck and the bullet ogive. neck wall thickness, too.
I don't have one of these gauges yet. I know which one I want to purchase, just waiting for the money to pile up. Although the dies I'm using have the size bushing that coincides with my neck wall thickness. I'm also using Remington brass. I have a box of Lapua but I'm still perfecting my fireforming routine and I don't want to accidentally sacrifice any of it.

you don't mention the barrel... is it a punched out factory tube, or is it a custom? that alone makes a world of difference. trigger? scope? action work? stock?
It's a Cooper rifle, free floated bull barrel, two pound crisp trigger, Leupold 6.5-20X40mm scope and wood stock. No action work yet as I've only had the gun a few weeks. The rifle is guaranteed half inch at 100 and that's exactly what I'm getting. But....I know I can do better than that, I'm just unsure of the process to get there....hence my questions.

Have you tried different seating depths?
Yes, I have. With one powder/bullet/case combination, I found the amount of propellant that shot best then started playing with OAL. I started with the bullet at the lands and moved back in .005" increments. I usually shoot two groups and average out the group size to see which one is best. So far, the gun appears to like the bullets farther from the lands. With the Sierras, my tightest group was with cartridges with shorter OAL.

Bullets. Maybe sierra 69 bthp? Maybe some berger flat base? The manufacturer specfies that with a 1-14" twist rate a maximum of a 50 grain bullet should be used. I have contemplated going to a 40 grain BlitzKing although the Bergers are on my short list of things to try.

In your shoes, I'd drop the charge 5%, and seat with the bullet 0.005" back from "jam length", then start groups at 0.005" further back, progressively. Once you find the seating depth it likes,then start increasing the charge.
Am I doing it incorrectly by varying propellant first? What is the reasoning behind OAL first, then charge weight?

The shooters rifle-handling skills are also approximately equal. most of the time, the winner will be the guy who read the conditions the best. Sigh...I know nothing about reading the conditions. It sounds as if I better attend a match or two to learn me some stuff... :p

I am shooting the gun off a Sinclair windage adjustable rest with a rabbit ear rear bag. I don't think my goals are unreasonable but I was really stumped on what to do next. I just figured I'd start doing the bullet/propellant shuffle and mix and match components until something works.

Ed

dakotasin
February 24, 2005, 06:06 PM
bullets... they are holding you back here. at least move to a matchking. the 223 ack should generate enough velocity to stabilize the 52 mk's in the slow twist. also check on hornady v-max and a-max... i get better accuracy w/ a-max's than i do any other 'common' bullet.

run-out... spring for the rcbs casemaster. it will give you more data than you'll need.

i think that between switching bullets and measuring run-out another tenth of an inch will be easy to get.

use the run-out gauge to help you set your dies up. after you get done sizing your cases, check the neck run-out. all the ones w/ .002" or less will be great. after you get done seating bullets, measure run-out on the bullet ogive. .003" or less are good to go. between segregating by weight and then by run-out, you should be able to already see how many cases are going to be discarded. if you want to get even more anal, you could index your cartridges by run-out... i'm not convinced this helps, but some claim it does.

are you deburring primer pockets? no hard evidence to suggest this helps, but enough anecdotal evidence that it is something i do.

while your trigger is great for a hunting rifle, recognize that it is extremely heavy for a target gun...

esheato
February 24, 2005, 07:28 PM
the 223 ack should generate enough velocity to stabilize the 52 mk's in the slow twist. also check on hornady v-max and a-max... i get better accuracy w/ a-max's than i do any other 'common' bullet.
I'm pushing a mild 3400 fps right now. I will pick up a box of the 52 grain MK along with some Berger 52 grain MEF and standard bullets. I've played around with the Hornady V-MAX and had the same luck as I did with the BlitzKings. Half-inch groups were common but that was all I could do with them.

are you deburring primer pockets?
No, I had never even contemplated it. What's the benefit? Could ya point me to a spot on the web?

while your trigger is great for a hunting rifle, recognize that it is extremely heavy for a target gun
I was considering getting some work done to it. I guess I should give my smith a call.

One more thing...would it be worthwhile to start using the Lapua brass I have on hand rather than weighing and sorting through hundreds of Remington?

I really, really appreciate all the help. Gives me more stuff to get fanatical about. ;)

Ed

The sad part is that I had ordered a box of 500 BlitzKings a few days ago and they just arrived... :rolleyes: They will work great on squirrels though. Half inch at 100 is good enough to shoot varmints out to probably 300 yards. I'll let ya know how they work on squirrels after this weekend. :)

dakotasin
February 24, 2005, 08:37 PM
ok, i'm not very good at posting pics so hopefully this will work...

the tool is like a drill bit at the end, w/ a handle and stop collar on the other end. you determine how much brass you want to remove from the flash hole on the inside (through trial and error), set your collar, and then twist out the garbage around the flash hole. you should note this is not necessary w/ lapua or norma brass as their flash holes don't have the garbage around them that win/fed/rem do.

as far as a spot on the web, you'll have to search br central. i know its been covered in depth there, but might've been lost when they did the forum switching, don't know for sure. the tool costs less than $10.

yes, if you have lapua on hand, you should be using that now.

consistency is what makes accuracy. every case, every bullet, every primer, every powder charge, shooter, and rifle quality...

i've never taken a cooper apart, so don't know how they handle the bedding. but, note that br shooters typically glue their rifle into the stock (glass bed without release agent). i don't condone this practice, but bedding might help ya.

realize, your rifle is guaranteed to shoot .5" at 100, and it already does that. while it might be possible to squeeze more out, you are running out of 'easy fixes'...

esheato
February 24, 2005, 08:52 PM
are you deburring primer pockets?
I've never deburred primer pockets, but I have deburred flash holes. Mincing words I'm sure, but we're talking about the same thing.

I do have that tool and already do that procedure to all my normal commercial brass.

br shooters typically glue their rifle into the stock (glass bed without release agent). i don't condone this practice, but bedding might help ya.

Very interesting. I had no idea that they did this.

I'll have to workup the Lapua brass next week as I'm about to leave town tonight.

while it might be possible to squeeze more out, you are running out of 'easy fixes'...

I'm starting to realize this. Hopefully with a simple bullet change and some judicious sorting (neck and ogive runout measurements) I should be able to get down a little bit more.

Thanks again and I appreciate the PM also.

Ed

dakotasin
February 24, 2005, 09:11 PM
oops... i made a boo-boo re: the deburring...

deburr flash holes, uniform primer pockets.

sorry! good luck!

esheato
March 29, 2005, 06:39 AM
AN UPDATE...

I picked up some 53 grain MatchKings and loaded them with Hodgdon H322. Propellant ranges were from 24.0 to 26.5 in half grain increments. I used QuickLOAD to examine the loads before actually firing them. According to the program, the 26.5 loads were a max load but I would be working up to it.

Using Lapua brass and the match bullets, my twelve group average was .586".. Although the average doesn't really show the improvement, I had one group in the .300s and three in the .400s. If you were to look at the groups, they're significantly tighter....and usually only one bullet is pulled out of the group...by me. :uhoh:

One interesting thing did happen. I began shooting the 26.0 grain loads and immediately had sticky bolt operation, brass flow into the ejector on the bolt, slight cratering of the primers...needless to say I stopped after the first one and I've been pulling bullets tonight. Good thing I only loaded fifteen of 'em. ;)

I do believe that I am going the wrong direction weight wise though. Call me stubborn but I had to see for myself. My next step is 40 grain BlitzKings and Bergers and a concentricity gauge. That's a little bit down the road though.

Ed

Dave P
March 29, 2005, 09:00 AM
Ed, did you calculate the Optimum Barrel Time for your rifle? Then plug that # into QL to give you a range of powder weights to start testing.

I have had very good coorelation between calculated OBT's and results on target.

Dave

bogie
March 29, 2005, 10:09 AM
Campers, campers, campers... Here's what I'd do with a 6PPC...

Determine optimum seating depth - That means frost a bullet, put it in an empty unprimed sized case, chamber it, and measure it from head to ogive. Don't bother about the point. Back off about 0.005".

While you're at it... Go to www.benchrest.com to bullets, and look for Bart's web site. He makes some very nice .22s that will work fine for varmints. Trust me.

How heavy is your trigger? Do you have to touch the rifle to shoot it?

Is your scope reliable?

USE WIND FLAGS.

How often do you clean? Use a bore guide and Butch's Bore Shine.

On a calm day tack up a sheet of paper, start low, fire three shot group at 200. Add little, fire another next to it. Repeat. Look for when the vertical closes up. Those are your tuning nodes. You do not have to shoot the hottest load.

esheato
March 29, 2005, 10:37 PM
Ed, did you calculate the Optimum Barrel Time for your rifle?
No. I guess I should have read the manual. :p I just searched the user guide and don't see anything regarding it. Can you point me in the right direction?

Bogie, I'm not sure what you're talking about. I don't even own a 6PPC. I did answer a bunch of your questions in some of the above posts though. I'm not even concerned about the wind yet...just trying to get my load practices down.

Ed

macavada
March 29, 2005, 11:19 PM
bogie:

What does "frost a bullet" mean? (Please bare with me, I'm learning.)

Bullet
March 29, 2005, 11:26 PM
I believe bogie is referring to a way to coat the bullet so when it touches the lands the lands will leave a mark on the bullet. Some people use a magic marker others use smoke from a candle (not sure about frost).

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