View Single Post
Old September 28, 2012, 08:25 AM   #5
Bart B.
Senior Member
 
Join Date: February 15, 2009
Posts: 8,927
I've only worked up one load in my life of wearing out many barrels. That was for the .264 Win. Mag. For the .30-06, .308 Win. and a couple of 30 caliber magnums, I just used the same load recipie others have used to win the matches and set the records. Those loads were good enough to shoot as accurate as anybody elses, so why wear out a barrel or two trying to improve on it.

If one shoots 20 or more shots per test group, I'm convinced they'll get much better confidence levels than what 5 shots in a group show. What convinced me of this is when I let a dozen or so folks shoot one of my scoped .308 Win. match rifles from a bench at a public range. That rifle and the ammo used would shoot into 3 inches at 600 yards; 1/4 inch or better at 100 yards. Those folks shooting it using their bench techniques had 5-shot groups at 100 yards ranging from 3/4 inch to almost 2 inches.

So, in my opinion, no wonder there's hundreds of "best" loads out there for a given bullet in a given cartridge. I also believe that one will get much smaller test groups if they learn to shoot from the prone position with a bag under the stock fore end and another under the stock toe. Us humans are much more repeatable in how they hold a rifle this way than from a bench. Even the benchresters don't hold onto their rifles' fore ends pulling the stock back into their shoulders as it rests atop something on the bench; they know that's not a good way to get best accuracy.

And I think one should also use the largest group fired as the accuracy for a given load; that's what can be counted on most of the time. The smallest groups shot are seldom equalled again.

PS:

I'll add one more intersting thing about measuring anything. If one doesn't get the same results each time, their measurements ain't very accurate. So, it also applies to measuring groups of shots assessing a rifle's or ammo's accuracy. If all the groups with a given load ain't the same size, they are not a very good assesment of the accuracy it produces. Remedy? Shoot more shots per group until they're all about the same size. . .within 10% or so at least. Best example's averaging several few-shot groups. If all the groups were shot atop each other, they many group composite would very well accurately measure the rifle/ammo accuracy. It would also be larger than the biggest few shot group fired.

Last edited by Bart B.; September 28, 2012 at 06:44 PM.
Bart B. is offline  
 
Page generated in 0.02168 seconds with 8 queries