MINOR CHANGES DON'T AFFECT ACCURACY Yesterday the guy at the next bench was shooting a Ruger bolt gun in .257 Roberts, a rifle he shoots frequently. He is an experienced reloader and shooter, shoots a variety of bolt guns in a variety of calibers from .223 Rem. to some .338 horror that makes my ears ring. He's been around the range for years. His Ruger was shooting 5 shot 100 yard groups of 4” to 2+". The scope was Swarovsky, ??, he said he paid >$1100 for the scope. The sporter barrel wasn't clse to the stock-big gap/free floating. We spoke and he calculated that he had fired >800 reloads, plus perhaps 200 factory rounds through the rifle. (He notes the number of times each lot of brass has been fired, and got the >800 reload number from his records.) Yesterday he had loaded 50 with 100 grain bullets and varying amounts of powder. Now this guy is smart and experienced, and he finally admitted that he was screwing around, making minor changes and searching for the accuracy trick. We talked about me shooting jacketed bullets seldom and only to check that a barrel WILL shoot before working to get it to shoot lead. We agreed that any newish rifle in any reasonable caliber with any reasonable book load will shoot jacketed into 1.5” 5 shot 5 group averages at 100 yards-with many combinations doing much better. He explained that his rifles shot accurately, that (jacketed) accuracy was easy, and that the .257 Ruger was a challenge. He ain't going to get there with minor changes. And cast bullet shooters ain't going to get there with minor changes. There's a simple recipe, a cookbook, that gets a cast bullet shooter to the 1” level-it is simple and easy to get there. The recipe doesn't include neck tension or primer pocket depth or .1 grain powder charge variation or weighing bullets or annealing gas checks or orienting anything or segregating anything. It ain't about “sweet spots” or barrel harmonics or bullet hardness/pressure relationships or any psuedo-scientific legend. There's no reliable data that I've found defending any of these myths, and I've been looking for years. And, the mathematics proves that minor changes are minimized or obscured in the major changes; that if there is a signal, it's lost in the noise. It is now time to mention the absolute fact that Leonard Knurlman, champion cast bullet shooter, always aligns primer anvils with the headstamp so that the top anvil leg is always perpendicular to the earth's surface. To which I respond:"He also eats calves liver for supper every Wednesday". The primer anvil alignment has as much to do with Leonard's accuracy as the calve's liver. We do a disservice to our fellows when we staunchly defend some accuracy trick that SHOULD BE TRUE when there is no evidence that it IS true. I believe that we have a responsibility to differentiate between BS and the real world.
MINOR CHANGES DON'T AFFECT ACCURACY
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- Last Post 03 July 2014
Well said, Joe, especially the last sentence!:dude: Confusing cause & effect with coincidence, (Post hoc, ergo propter hoc) is an age old problem, as is ascribing factuality to what is merely plausible and unproven.
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I do the calves liver, but not on Wednesdays. Maybe if ...
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I concur 100% Joe.
LMG
Concealment is not cover.........
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I look for the words “this is what works for me” and group sizes in fractions of an inch (not terms of 'amazingly accurate' and such).
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I look for the words “this is what works for me” and group sizes in fractions of an inch (not terms of 'amazingly accurate' and such).
I haven't stepped on a sidewalk crack in over 11 years and none of my barrels has had a chamber ring in that time. This is what works for me.
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I look for the words “this is what works for me” and group sizes in fractions of an inch (not terms of 'amazingly accurate' and such).
I haven't stepped on a sidewalk crack in over 11 years and none of my barrels has had a chamber ring in that time. This is what works for me.
Keep watchig your step! THAT works for ME. :)
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I want that recipe. Most of my rifles shoot 2” 10 shot groups and I'm glad.
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I want that recipe. Most of my rifles shoot 2” 10 shot groups and I'm glad.
BEGINNER'S RECIPE FOR CAST BULLET RIFLE ACCURACY Shooting cast bullet five shot five group 100 yard averages between 1.5” and 2” is easy. This isn't the best or the only or the least expensive recipe; it is a recipe that will produce the stated accuracy. The shooter must have one or more reloading manuals, the equipment needed and a modest amount of experience. Notebook: Maybe the most important item Rifle: Savage with accu trigger in. 308 Win. (I'm partial to Savages, other rifles will work.) Sight: Any good Adjustable Objective scope starting at 3-9 X set at 9X. Midway sells a Simmons Whitetail Classic 6.5-20 X scope for ~$110 that is about 90% as good as the best scope made. Rest: Any stable home made or bought rest and sand bags. Brass: 100 new commercial Remington or Winchester cases Bullet: Lyman 311299 or 311041 Alloy: Wheel weights or WW + tin or Lyman #2 Lube: Any Lyman lube or Lee Liquid Alox Primer: Remington or Winchester Large Rifle Powder: IMR 4227 Charge: 18-23 grains Full length size and trim the cases to length, chamfer the case mouths in and out. Bell the case mouths.Inspect the cast bullets for obvious defects, re-cycle the defectives, put on gas checks, size to diameter between .312” and .309” and lubricate.Find the maximum overall length for the cartridge.Prime the case, throw the powder charge, inspect the powder level and seat the bullets.Fire the cartridgesMeasure the groupsA bullet MUST slide into the fired case mouth with little resistance. If not, turn the case necks.WRITE EVERYTHING DOWN!Vary the powder charge and/or bullet diameter to improve accuracy.A diligent shooter will soon be shooting one inch 100 yard five shot group averages.
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Recipe test.I'm short on IMR4227, but....I screwed a new-to-me 22” sporter .308 Win barrel on a Savage 10, 314299 sized .309", 14/A#9, WLP, 2.815” loa, Lyman Super MolyI'll try it Wed., it should avg <1.5” if the barrel is OK.
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Recipe test.I'm short on IMR4227, but....I screwed a new-to-me 22” sporter .308 Win barrel on a Savage 10, 314299 sized .309", 14/A#9, WLP, 2.815” loa, Lyman Super MolyI'll try it Wed., it should avg <1.5” if the barrel is OK.
I loaded 30 with sighters = not-perfect-bullets. Got on the paper, then 4 groups.1.25, 1.7, 1.3,.7; avg = 1.24-all inchesalso had anoter 29, perfect? bullets.95, 1.35, 1.35, 2.35?, 1.9; avg is 1.58-all inchesThe average vor 9 groups is 1.43", 5 shot 100 yard groups, Weaver T36, $50 light 22” sporter barrel. First time I ever shot the barrel.Cast bullet accuracy is EASY-follow the recipe.
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my hero ..
kenSo many people feel the same way. Thank the Lord that my shoulders are broad.
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The word “match” is a verb, as well as a noun. Your best bet is to have all components as closely matched as possible. “Tolerance” is the acceptable range of specifications, but if you're at the top of spec on one component, and at the bottom of spec on another, you can induce variables that rob you of performance. Tolerance stackups or tolerance stacks are terms used to describe the problem-solving process in mechanical engineering of calculating the effects of the accumulated variation that is allowed by specified dimensions and tolerances. (swiped from Wikipedia)
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The word “match” is a verb, as well as a noun. Your best bet is to have all components as closely matched as possible. “Tolerance” is the acceptable range of specifications, but if you're at the top of spec on one component, and at the bottom of spec on another, you can induce variables that rob you of performance. Tolerance stackups or tolerance stacks are terms used to describe the problem-solving process in mechanical engineering of calculating the effects of the accumulated variation that is allowed by specified dimensions and tolerances. (swiped from Wikipedia)
Good point. Well understood by those in manufacturing. I think what joeb was saying was that if it doesn't affect accuracy much it is a minor change.
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gauge standards. ok, here's an embarrassing story, but perhaps will clarify the reason for gauges ... lika those headspace gauges ... a big customer wanted some shock absorber cylinders and sent me one adjusting nut to fit threads to ... knowing better is what hurts ... after a few hundred cylinders with cnc identical threads to match the nut the customer found that he had sent me an oversize nut ...none other nuts fit my non-gauged cylinders. note i said MINE. anyway it is good to fit chambers with a real headspace gauge.
ken
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oh, i forgot another point of my embarrassing story ...
which is better ... to have 500 perfectly cast exact weight matched,castings which don't fit the throat ...
or 500 half-frosty, slightly out of round .. slightly dimple-nosed ...weights varying 3 % ... but are a clone of the dimensions of your throat y leade ?
as someone told me ... data points accepted ...( g )
ken
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oh, i forgot another point of my embarrassing story ...
which is better ... to have 500 perfectly cast exact weight matched,castings which don't fit the throat ...
or 500 half-frosty, slightly out of round .. slightly dimple-nosed ...weights varying 3 % ... but are a clone of the dimensions of your throat y leade ?
as someone told me ... data points accepted ...( g )
ken Well with the bullets that fit the chamber one won't need a hammer to close the bolt. Had that happen in a match. Also, after “hammer fitting” the bullets.... they don't hit close enough together on the target.
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Joe, what you write is, to me, the most concise essay I can remember reading about how to get decent groups, without the discouraging number of cast bullet sessions with complete misses, and “I don't see it on the paper, wonder just where the Hell it went” shots that make it so tempting to just quit and go back to jacketed. Along with this is John Alexander's well crafted writing about how we tend to over-complicate the process, thereby possibly discouraging newcomers. The two essays by you gentlemen work well together. (About John's essay, I have a great example of just what he's saying; I wrote about it on another section of the forum.) Bill
In theory, there's no difference between theory and practice. In practice, there is. My fate is not entirely in Gods hands, if I have a weapon in mine.
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Just because you wear bells in bear country and you don't get attacked doesn't mean there afraid of bells gp
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