What is the Most Promising Aspect of CB Rifle Shooting for Improving Accuracy?

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John Alexander posted this 18 January 2020

CBA has been partially responsible for the progress we have made in shooting CBs in fixed ammunition (as opposed to breech seating) over the last forty years but that progress has mostly stopped.  Those shooting specialized custom rifles with no restrictions cannot consistently shoot aggregates of 5-shot groups much under 0.5" at 100 yards.  Those of us who like to shoot unmodified factory or old military rifles cannot consistently shoot 5-shot aggregates much under 1.0" at 100 yards. We have been able to shoot to this level of accuracy for at least ten and maybe twenty years with little improvement.

The first of the four stated "purposes" of the CBA on the back of every Fouling Shot says: encouraging experiments that will improve the accuracy and effectiveness of the ammunition and increase the satisfaction and enjoyment of shooters. Many, probably most, of us that shoot CBs in rifles want to improve either to enhance our competitiveness if we like to shoot in matches or simple to do better for field use or personal satisfaction if we don't. 

What is the best way to achieve that improvement?  Up until now many have thought that uniformity was the road to improvement.  Ever more uniform weights of cases, powder, bullets, even gas checks and primers, ever more uniform sizes of bullets, flash holes, primer pockets, ever more cleanliness of bores, case necks, primer pockets and inside cases. Other efforts at improving uniformity have included using only one case, using nose pour molds or turning bases to achieve perfect bases, shooting bullets in the order they were cast, indexing bullets, cases and even primers.

It is hard to argue against uniformity but easy to see that more and more isn't always better and some of the above have been grossly overdone and achieved nothing.  Many of our best shooters have found many of the extreme attempts for uniformity listed above were worthless and have abandoned them. 

Paul Pollard has asked in the thread on factory ammunition what should we be working on to improve?

Because we have already tried pursuing uniformity to the point of foolishness, that approach doesn't look promising for future improvements. I hope we can start a discussion on what are some of the promising ways that should be explored in order to shoot CBs more accurately? What do you think?

John

 

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4and1 posted this 06 March 2020

Ken, I hear ya! What you posted is the reason I don't shoot RF benchrest! Jacketed benchrest is enough to make you go after adult beverages, but RF, I think, is far more frustrating. We (J guys) can change things, RF guys have to shoot what's in the box.  And don't get me started on the tuner thing. I know tuners in RF are probably as important as a good scope, but some have used them in the J crowd. Adds another thing to futz with.

I suppose I should add to my other post, but doing these 3 shot tests point you in a direction to follow. They aren't proven. In my view, and I have learned this the hard way, a gun/load is not proven until you shoot an agg with it. I laugh at the guys who pull out this target from their wallet and say "lookie here". I say, how many times have you done it?  While I have talked about keeping the gun in tune during the day, that's not the same thing as proving the gun over a 10 target agg. Each and every piece of that rifle plays a part in the final result. If they aren't working in sync, the gun won't shoot well. And what Ken says about buying barrels from other shooters, is true. Thes J boys change barrels like most change underware. One bad match, and that barrel can be had cheap! And that same barrel, installed on a different action/stock, could very well be a killer!

Aint this fun?

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John Alexander posted this 06 March 2020

Great post Ken.

This part will be ignored by almost everybody but it shouldn't be.--  "we also shot initial 3 shot groups when checking the tuner settings .. we eventually discovered what JoeB has been telling us here for several years in his revelations of statistical hard truths. our three shot groups were not telling us the best tuner settings, they were only telling us if a setting was really really bad."

----------

Absolutely! maybe even three reallys instead of two. Even a great load  sometimes shoots a big three shot group and not that seldom. 

I think much of the systematic load development work, like ladder testing and such, that shooters do doesn't amount to a fart in a whirlwind because shooters forget (or never have recognized) just how much three or five shot groups vary from one to another and make decisions based on a few groups. It takes really huge amounts of ammo and time to do something like a ladder test to a reasonable confidence level. 

Shooters who make decisions on the best loads by shooting a five or ten shot group for each load are probably not going to find the best load.  Shooters could profit by spending some time staring at, and thinking about, the table #5 (Variation in Group Sizes) Joe provided in the thread Statistics and Groups a week or so ago.  This drill might help give a shooter a better sense about the probability that an individual group, or string of groups, is telling the truth.

John

 

 

 

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Ken Campbell Iowa posted this 06 March 2020

4and 1 ::   great stuff .  fits right in this thread.

we keep buzzing around the problem/answer of better cast accuracy ... kinda like those flies we hear about ... heh .

**************

your described testing of br jb loads mirrors the " testing lots " of 22 rf with our match rifles.  we tested brands, then lots, then barrel tuner settings.  we bot ammo by the 5000 round case and shot almost all of it testing ... the most fun was talking about  IF and WHAT we had learned .

we also shot initial 3 shot groups when checking the tuner settings .. we eventually discovered what JoeB has been telling us here for several years in his revelations of statistical hard truths.

our three shot groups were not telling us the best tuner settings, they were only telling us if a setting was really really bad.  we knew we could shoot 500 shots and our group would be under 0.4 ( at 50 yards ) ... so if a tuner notch gave us a 0.6 group we knew that on that day not to use that setting.  yep, a 3 shot group is just part of a larger ... say 150-300 shot group ( that we would shoot in a match ) .

so after we ran through maybe 20 of 3 shot testing groups we had to go back and shoot 2 or 3 complete 25 shot targets with each of our best-guess tuner settings.  that setting would be good for that day in those conditions.   we tried to pick a notch that gave good groups a click or two each side of optimum, thinking that would be more likely to be close in other conditions.

the ammo makers love 22 rf shooters.

*************

we did find that ... contrary to all those gun magazine articles where they test 70 kinds of 22 ammo to find " which ammo their rifle likes " ... that ::

the best ammo shoots best in all the rifles.... once the tuner setting is found.  this is an observation, i am not sure what this might mean.   ... all 40 cent a shot midas L looks exactly the same ... but some lots shot better regardless of the tuner setting ... or chamber variations or headspace settings or barrel maker or twist ... 

this probably gives credence to the obsessive powder grain-counters ...  but it still doesn't give us predictable groups under 1/2 moa with cast.

*************

just to make ourselves feel better, i do follow my heroes that shoot mj bench .. i delight that even at the big matches, where yep the winners shoot a lot of 0.1 groups ... but there is a whole bunch of 0.4 and even a few 0.6 groups ... in fact, i buy an occasional shilen/hart barrel from some of those " non-winners " ... heh, have got about 30 of these now that i put on local varmint shooters rigs.  they get a few ( lucky ) 0.4 inch groups at 200 yards and so the technology gets passed on .

***************

just ramblin'  ken

 

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4and1 posted this 06 March 2020

John, thank you! If you notice in my post I mentioned not many being at the top of the list, well I'm not one of those at the top! I have not learned the fine art of  keeping the tune. When I travel to a match, I go a day early and spend time on that range working on loads. Every range is different. At the end of the day I would feel confident I had the gun shooting as good as it could. Then the next day when the match starts, I couldn't make two bullets touch. Or, I would start out and shoot a couple good groups, then the tune goes out and I'm shooting .3's the rest of the day. It can be frustrating.

I will say though, and no offense toward others, not many people take the time to work up a load for the gun/bullet/powder in a methodical way. There is a process, it takes time, but it will show you what your gun wants to shoot. Every rifle creates vibrations when it goes off, and you have to find where you can get the vibrations to a neutral node, otherwise shots go everywhere. There are two aspects of a load, powder charge and seating depth, considering the brass is prepped and the barrel is clean. Side note, I know some cast shooters hardly ever clean, to each his own. But when I go the the line, I want my barrel in the same condition each time. I won't shoot more than 10-12 shots on any target. The only way to know this is to start every target with a clean barrel.

Find the depth where the bullet just touches the lands. With a piece of brass that is sized enough where there is no feel when closing the bolt (firing pin removed, ejector removed) seat your bullet and slowly chamber the round. If the bolt closes on it's own weight the bullet is seated to far into the case. If the bolt won't drop then the bullet is seated against the lands. Carefully seat the bullet a small amount until the bolt will almost drop closed, not fall, but start to lock up . There is where you have touch, this is ZERO setting.

Powder charge- with your powder of choice, start with a light charge, for sake of discussion, let's call that 25 grains. Set a target that has a bunch of rows of bulls. Make up something on the back of a normal target, you want 3 bulls wide, and quite a few of the rows down the paper. So here we start:

With the seating depth at ZERO, load a fouling round just to shoot off the side, load 3 rounds with the light load, 3 with a medium load and 3 with a heavy load. You decide if the load difference is by grains (how many grains if need be). Shoot the 3 light in the first bull, 3 medium, 3 heavy.

Next row, from the ZERO depth, seat the bullet .010" into the lands, load the same 3 rounds each of the 3 charges.

Next row move the bullet another .010" into the lands (.020" total), shot the same 3 shots of each charge.

Next row go back to ZERO, but this time seat the bullet .010" into the case, shoot the 3 loads

Next row seat another .010" deeper (.020" total into the case) shoot the 3 loads.

You should see a difference of the groups. You should see a pattern somewhere. It may be the powder charge or seating depth that shows better groups. Follow what shows best. It may be the farther into the lands were getting better, so chase that and see if more is better. Or powder charge, you might need to go faster or slower. But what you should see is what the gun likes or doesn't like. If you didn't run a test like this, you would never know. .010" may be too much of a change, cut it in half. Same with powder charge, go between to fine tune. It takes time, but it's worth it.

Sorry for the long post, didn't know how else to explain it.

I'm adding a comment here. In short range benchrest most likely you are shooting either a 6PPC or a 30BR. In both cases, powder type and charge are tried and true, usually only some tweaking will be needed.  When I started cast, I went through the match results and noted all the powders and charges people had listed. That was a good starting point for sure, and I tried all of them. Some did OK for me, some were a flop. I zeroed in on a burn rate that seemed to work, and concentrated on powders in that range. Powders have more of a characteristic than a burn rate, as far as burn rate charges go. Even in the same range of powders, some still work better than others. Don't be afraid to go outside the box.

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John Alexander posted this 05 March 2020

4and1,

Excellent post. You mentioned temperature and humidity changes.  Whatever effect they have on jacketed bullets they may have even more on cast bullets. Increasing or reducing a load in anticipation of temperature on the day of the match is obvious although how much exactly isn't so obvious.  What wisdom did you learn from your JB benchrest friends about compensating for these changes in conditions. i don't think most of us CB competitors have a clue although maybe it's just that I don't have a clue.

I think you will get a lot of support here for your opinion that the bullet is most likely the weakest link, but again what to do about it"

Many CBA competitors already weigh sort their bullets to .2 or even .1 grain for 200+ grain bullets (0.1% or 0.05%)  Berger match bullets vary several times that percent variation and shoot better than any CB. We stew about hidden voids but with good casting practice it is not certain that they really exist.  There is no test results to support the idea that such things as examining bullets under magnification to pick up visible defects that can't be seen with our trifocals does any good. Matching the chamber pressure to the appropriate hardness has been mentioned here by 45 1.1 and others, but many of us have been trying to do that forever.

Any advice you have from your experience with jacketed benchrest would be valuable.

 

 

 

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4and1 posted this 04 March 2020

I'm fairly new to cast bullet benchrest. I do however have over 25 years of shooting both score and group benchrest with jacketed bullets. I have competed against the top shooters in this country (note I said competed against, not beat!). We all have guns that have the best of the best gun components, we use the best of the best ammo components. So why do some always end up at the top of the results and most are below them? Those at the top know how to keep a gun in tune. They change their loads from the first warmup match to the last target of the day. They know how to deal with temperature changes and humidity changes. Those here that have that some days you do good and the next day not so much. Well there is your reason.

But, one thing is a given. You cannot tune a gun, you cannot properly hold off from the last shot on paper, unless you KNOW your last bullet shot where it should have. What I mean is, if it were a flier and you took that as full value, your next shot based on that one will be wrong. You can't have UNEXPLAINED fliers and shoot a great match. If a shot goes out of your group, you have to know it was a missed condition, not a bad bullet.

I agree with all here that believe bullets are the biggest culprit to inaccuracy. I swage my own jacketed bullets. The cores must be pure in their alloy since they are squirted by size/volume. The jackets must have very little to no wall thickness variance (.0003" or less). And your dies must be good, they all are not made equal. The process and lube in swaging must be the same. Good bullets fly true, a flier is caused by conditions or out of tune load.

So in my opinion, it's the bullets, assuming the gun is capable.

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OU812 posted this 01 March 2020

Adjusting for throat errosion. Bumped bullet must fit perfect and little changes can help or hurt. It is very hard for me to mail down.

True linotype (roto metals) and higher velocities along with bumped bullet fit has shoot the smallest groups for me. Oh...and old long cut 4198.

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OU812 posted this 01 March 2020

Sorry...I was working nightshift and feeling a little silly when I made that comment, but I bet it can still out shoot all of you.

Just kidding. Need to get back to range.

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David Reiss posted this 01 March 2020

I bet my little 223 will out shoot all you guys.

I bet my vintage Red Ryder will out shoot your .223 @ 500 yards, I can beat you 9 times out of 10 arm wrestling, my bank account is 5 times bigger and my feet don't smell bad like yours, but this is all my opinion. 

My suggestion is that you re-join the CBA and shoot side by side matches to prove your opinion on your .223. 

David Reiss - NRA Life Member & PSC Range Member Retired Police Firearms Instructor/Armorer
-Services: Wars Fought, Uprisings Quelled, Bars Emptied, Revolutions Started, Tigers Tamed, Assassinations Plotted, Women Seduced, Governments Run, Gun Appraisals, Lost Treasure Found.
- Also deal in: Land, Banjos, Nails, Firearms, Manure, Fly Swatters, Used Cars, Whisky, Racing Forms, Rare Antiquities, Lead, Used Keyboard Keys, Good Dogs, Pith Helmets & Zulu Headdresses. .

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harleyrock posted this 01 March 2020

Coatings research:  Federal Syntech.  Surely Federal has done extensive research before setting up the logistics for producing coated lead alloy bullets commercially at a profit.

I don't keep good records, but I'd bet Federal does.  I would freely share any useful data (if I had any). I'd bet Federal wouldn't.

Lifetime NRA since 1956, NRA Benefactor, USN Member, CBA Member

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OU812 posted this 01 March 2020

I bet my little 223 will out shoot all you guys.

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John Alexander posted this 29 February 2020

Thanks for the table Joe, That puts in in perspective.

If you latest entry of 2017 means you don't have the breakdown of scores from 2018 and 2019 I will be glad to send them to you.

John

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John Alexander posted this 29 February 2020

Sorry about bringing JBs into the conversation. What I was trying to say politely in my last post, I will say in plain language.  When you see a keyboard shooter on the internet say he can shoot 0.3 moa with cast bullets especially if he claims doing it with a sporter type factory rifle there are two possibilities.

1. He has shot an occasional group that size and doesn't understand that such lucky groups aren't the same as actually being able to shoot at that level. 

2. He has been smoking or ingesting something that distorts reality.

We should be tolerant and kind.

John

 

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joeb33050 posted this 29 February 2020

 

If you're talking abouit under .4; then CBA NM:

 

 

 

 

 

But with cast you can do just about 0.3 MOA with a correctly fitting bullet alloyed for the load. Even a couple of long bodied Lyman numbers will do that when loaded right. 

=======

45 2.1 is right it is no big deal to shoot 0.3 moa with cast even I have done it with my hunting rifle.  There are usually a bunch of such groups at every CBA nationals. And of course its not rare on the Internet.  But a 0.5 moa aggregated will almost always take the gold in any cast bullet match anywhere and in the history of Am. Rifleman testing of a lot of high priced rifles I can't remember them every having achieved a 0.3 moa average and they are testing with several brands of jacketed bullet ammo -- funny abut that.

John

 

 

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45 2.1 posted this 29 February 2020

You can learn a lot following the other fellows game that you can't learn doing your own. Most people never see that. Cast a perfect bullet to begin with and the unnecessary regimens will be seen as that....unnecessary.

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RicinYakima posted this 29 February 2020

I know, that is why I quoted him.

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JimmyDee posted this 29 February 2020

John was referring to American Rifleman tests using commercial ammunition in his "[never] achieved a .3 MOA average" remark.

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RicinYakima posted this 29 February 2020

John:  "history of Am. Rifleman testing of a lot of high priced rifles I can't remember them every having achieved a 0.3 moa average"

45 2.1: "Go to a national level bench rest match in the jacketed realm, 0.3 MOA will not get you any notice"

You guys are starting to talk apples and oranges again.

I'm sick and having a hard enough time trying to follow all this conversation between the drugs and sleepiness.

 

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45 2.1 posted this 28 February 2020

 I can't remember them every having achieved a 0.3 moa average and they are testing with several brands of jacketed bullet ammo -- funny abut that.

John

Go to a national level bench rest match in the jacketed realm, 0.3 MOA will not get you any notice or awards and you'll place way down in the listings. They shoot down in the teens from what the two local shooters say.

 

 

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Ken Campbell Iowa posted this 28 February 2020

amongst my growing list of orphan shooting stuff are some bullets that might be of interest in testing; pm me if.

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