newbie- Loading .308, and soon .223- recommendations

[Bart B.]

OSOK, no, I don't live around Sibley, MO. But I've shot a bunch of their ammo and talked with their ballistics folks by phone a few times about their ammo when I was on a military rifle team. One lot of LC M118 match would shoot a few bullets from a box of 20 about 130 fps slower than normal; they would go in about 2 feet low at 600 yards.

[oldpapps]

See, I told you. how many people have ever hear of Sibley. Most think of Lake City as Indep or Blue Springs.

Nuff,

OSOK

[Bart B.]

Oldpapps asks me:

Is it not your opinion that the best accuracy for a given weapon is achieved by fine tuning the load for that weapon?

Yes, but only if it's worth the expense of doing it.

How many shots per test group for each load does it take to have 99% confidence that one load's 3% more accurate than another?

Note also that if you shoot two groups with the same load and they're not within 5% in size, you're not shooting enough shots per group for them to be at least 95% meaningful. Best example of this is shooting a few 5-shot groups then averaging their size. The average is not the accuracy of the load. The accuracy is at least the size the largest group is. If you fired one 20-shot group instead of four 5-shot ones, that 20-shot one will be bigger than the largest 5-shot one.

[Mr.RevolverGuy]

In AR15 and AR10/223/308 I find H335 works very well and meters like water that delivers a consistency you need for accuracy. Though in the AR10 I get a slight flash out of the end of the barrel that I don't get with 223. When I run out of H335 I hear Reloader 15 is a good powder to use.