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- Thread starter mendozer
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If you want to see realistic changes in accuracy making .050" increments in OAL, I think you'll need to shoot at least 20 shots per test group.
Having worn out several .308 Win. barrels whose bullets seated to 1/16th inch short of the magazine length for OAL, the bullet's jump to the rifling increased about 1/10th inch over 3000 rounds. No significant difference in accuracy through 300 yards.
Same thing with M118 and M852 7.62 NATO match ammo all loaded to a given OAL for each, then shooting them in Garands that had the same 1/10th inch jump to the rifling distance change over their 3000 to 4000 round barrel life.
I don't think wasting ammo for best OAL for sporting rifles is all that important. And for match rifles, only loads used at 600 yards and beyond does it matter; even then not very much. If it did matter, then everyone shooting the same make and model of rifle would end up with the same OAL for each round with a given bullet. That doesn't happen; everyone gets a different number when the barrel's chamber dimensions are virtually equal.
Having worn out several .308 Win. barrels whose bullets seated to 1/16th inch short of the magazine length for OAL, the bullet's jump to the rifling increased about 1/10th inch over 3000 rounds. No significant difference in accuracy through 300 yards.
Same thing with M118 and M852 7.62 NATO match ammo all loaded to a given OAL for each, then shooting them in Garands that had the same 1/10th inch jump to the rifling distance change over their 3000 to 4000 round barrel life.
I don't think wasting ammo for best OAL for sporting rifles is all that important. And for match rifles, only loads used at 600 yards and beyond does it matter; even then not very much. If it did matter, then everyone shooting the same make and model of rifle would end up with the same OAL for each round with a given bullet. That doesn't happen; everyone gets a different number when the barrel's chamber dimensions are virtually equal.
I won't argue with the match shooters, about what gives the "best" accuracy, and the tips and tricks they use on their ammo to get there. They are some very experienced folks, and know what works and what doesn't for what they want.
I'm in a different place. I don't shoot matches, don't care a bit if the bullet drops subsonic at 600yds, or 800. I don't have match rifles. The closest I come is varmint shooting, and most of my varmint rifles are medium weight sporters, with the exception of my .22-250 M70 Varmint.
There is, for me, a clear difference between good, good enough, and the best you can get. Doing all the stuff to the ammo to get the "best possible" might be wasted effort shooting a rifle that will only do "good enough".
I see a lot of questions these days about COAL, and a lot of advice about how to find, and get what is "best". I believe that there is a "best" for some guns and uses, and there isn't one for others. What I care about is the loaded round works through the action (from mag to chamber) and the bullet doesn't touch the rifling.
Everything else boils down to what will be most worthwhile for you. If you are looking for minute of deer at 100yds shooting your .30-30 Model 94 or 336, the handloading steps that get you that sub MOA ammo probably aren't going to be of much practical value to you.
Seating the bullet "just off the lands" is good for accuracy, very often. But its not an absolute requirement for acceptable accuracy, not by a long shot, depending on what you are doing.
Weatherby rifles had (and may still have, I don't know current production specs) about a half inch of freebore jump to the rifling, and still they were considered the accuracy equal of standard sporting rifles in their class, if not a bit better, often.
Crimp is another example. You hear how crimp is "bad", how its not needed, how it spoils the accuracy, etc. And, they are all right, in certain specifics. But they aren't right for everything all the time.
Any time I hear "don't crimp" I think of tube magazine rifles and revolvers, where that advice DOES NOT APPLY. So take it all with a grain of salt, and figure out what applies to your situation, and your desires.
I'm in a different place. I don't shoot matches, don't care a bit if the bullet drops subsonic at 600yds, or 800. I don't have match rifles. The closest I come is varmint shooting, and most of my varmint rifles are medium weight sporters, with the exception of my .22-250 M70 Varmint.
There is, for me, a clear difference between good, good enough, and the best you can get. Doing all the stuff to the ammo to get the "best possible" might be wasted effort shooting a rifle that will only do "good enough".
I see a lot of questions these days about COAL, and a lot of advice about how to find, and get what is "best". I believe that there is a "best" for some guns and uses, and there isn't one for others. What I care about is the loaded round works through the action (from mag to chamber) and the bullet doesn't touch the rifling.
Everything else boils down to what will be most worthwhile for you. If you are looking for minute of deer at 100yds shooting your .30-30 Model 94 or 336, the handloading steps that get you that sub MOA ammo probably aren't going to be of much practical value to you.
Seating the bullet "just off the lands" is good for accuracy, very often. But its not an absolute requirement for acceptable accuracy, not by a long shot, depending on what you are doing.
Weatherby rifles had (and may still have, I don't know current production specs) about a half inch of freebore jump to the rifling, and still they were considered the accuracy equal of standard sporting rifles in their class, if not a bit better, often.
Crimp is another example. You hear how crimp is "bad", how its not needed, how it spoils the accuracy, etc. And, they are all right, in certain specifics. But they aren't right for everything all the time.
Any time I hear "don't crimp" I think of tube magazine rifles and revolvers, where that advice DOES NOT APPLY. So take it all with a grain of salt, and figure out what applies to your situation, and your desires.
If I found a load that shot like that in my hunting rifle I'd load up a bunch of those rounds and spend my time honing my shooting rather than trying to hone my load. The latter will pay more dividends in the field when you don't have to take that second shot or when you're able to confidently take an even longer shot because of the time you spent behind the gun.
Eric
I strongly suggest anyone shooting a few shots into a group they think is "tiny," please shoot a few more of those few shot groups. If they're all no larger than 10% bigger than that tiny one, then that load's proved very accurate. No rifle shoots the same load into groups the same size; the largest one is often 5 times as big as the smallest one. Which one in that range was your single few shot group at?
Remember that benchrest rifles that have shot record size groups also shoot ones that are pretty darned big. That record one's only the smallest one it shot.
Remember that benchrest rifles that have shot record size groups also shoot ones that are pretty darned big. That record one's only the smallest one it shot.
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I agree with Bart if your looking for what you and your rifle will likely shoot each time you pull the trigger especially if you plan to shoot in competition . I have a bunch of sub 1/2 moa 3 shot groups and .5 moa five shot groups , I don't have one .5 moa 10 shot group . Now I've not followed this thread perfectly so I'm not sure how many shots your firing in these groups . I assumed your shooting at least five shots per group . If so I believe that's enough to get a good idea what you will shoot with that rifle . How ever when I do load development . I shoot 5rd groups moving up in .5gr increments in charge weight from minimum . When I find a good load in those test . I then load 20 rounds of that good load and shoot two ten round groups . One rather quick ( 30 to 40 sec apart ) the other kinda taking my time ( maybe a minute or two apart ) . This often confirms the group was good but has never been as small as my smallest 5 shot group ( often 1/4 to 3/8 larger ).
If you only want to shoot 3 or 5 round groups , that's fine . What you can do is keep over laying the same type target perfectly over the last for each new group . When you're done shooting 3 or 4 groups take all but the very first target off leaving you with a very large group sample .
I'll add that I believe this has more to do with the shooter(me) then the load .
If you only want to shoot 3 or 5 round groups , that's fine . What you can do is keep over laying the same type target perfectly over the last for each new group . When you're done shooting 3 or 4 groups take all but the very first target off leaving you with a very large group sample .
I'll add that I believe this has more to do with the shooter(me) then the load .
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Rifles and their ammo shoot the largest groups just as often as they shoot their smallest ones. And the biggest variable in the whole shooting system is usually the human holding onto the rifle and loading the ammo it shoots.
If you look at the record groups in benchrest, their tiny, 5-shot ones are much, much smaller than the average groups sizes in many 10-shot group averages. The biggest group fired is often twice that of the average stated in the record.
If you look at the record groups in benchrest, their tiny, 5-shot ones are much, much smaller than the average groups sizes in many 10-shot group averages. The biggest group fired is often twice that of the average stated in the record.
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Metal god, I think I would overheat my barrel if I only waited 30-40 seconds before shots. Sporter barrel remember?
I was waiting like 2-3 minutes between.
As for the groups, I was doing 3 since that was the OCW method Uncle Nick referenced. I fully plan to shoot a bunch more though.
As for benchrest, that's not going to happen. This is strictly for hunting and target shooting with this hunting rifle.
I was waiting like 2-3 minutes between.
As for the groups, I was doing 3 since that was the OCW method Uncle Nick referenced. I fully plan to shoot a bunch more though.
As for benchrest, that's not going to happen. This is strictly for hunting and target shooting with this hunting rifle.