[Unclenick]

The guys have pretty much covered it, but I will have to point out that even in pistol you can see some differences. Many years ago, when the Army Department of Civilian Marksmanship (DCM) was still funded, on the pistol side of it, a number of competitors reported that the military match ammo was giving them higher scores than the civilian stuff. This was a source of puzzlement for a time. It was finally concluded that the pitch brushed onto military bullets as a moisture seal was adhering the bullets in place just hard enough to improve their ignition consistency.

If you've been shooting Bullseye (matches, that is), you'll already know this, but for others reading this who do not, the match accurized 1911 is nothing to sneeze at. When I first fit up my Series '70 Goldcup back in the early 1980's, despite employing the old fashioned method of welding up and filing and scraping the original barrel's link lugs to achieve lock-up, it's first group off bags was five shots into 0.37" C-T-C at twenty-five yards. That's just under 1.5 m.o.a., and not too sloppy for accuracy loading technique to be lost in the noise.

Knowing tightly fit match guns can do that kind of shooting and keeping the military ammo experience in mind, it is reasonable to assume that anything that affects neck tension on a bullet can be reflected on the target when shooting a tight gun. It needs to be consistent. I wouldn't start painting on pitch (what a mess), but I would make sure all the brass was the same make, did not have any wild weight excursions, and had all been reloaded the same number of times so work hardening of the brass (which affects that tension) is the same for any given reloading cycle. Mind you, even a 1.5 m.o.a. pistol is not going to have its group size halved by this technique, the way a 0.5 m.o.a. rifle might. But even if it were improved just from 1.5 m.o.a. to 1.4 m.o.a, that can turn into several additional points and X's over the course of a 2700 match.