I agree w/Miller's skepticism.
Its been a long while ago, but I want to recall that an article in Wolfe publications Handloader early on that dealt w/pressure & velocity testing repeated reloading's using an original AA CF 12ga. hull and it found that as the number of reloads increased there was a significant drop in recorded pressures as well as velocity. I know, there is no direct corollary between pressure and velocity and that was NOT being implied, rather it was simply observed as I recall. Hey, like Russ always said, I could be wrong. It may have been an article dealing w/crusher methods as well, i.e., LUP, not psi.
I cannot tell from the OP if it was factory loaded ammunition or something that had lead originally and the Nice Shot was used as a replacement. If it was the latter, that is NOT a proper application w/o tested data suggesting such use and it is an open question as to the pressures involved.
I've shot a lot of Bismuth, tungsten iron, Heavi-shot & steel and while the factory crimps on some of it has been 'butt ugly', I've never seen a crimp blow off, even in below freezing weather. Just my experience, not refuting Mike's at all. I don't shoot many Federal non-toxic loads though their newer Black Cloud loads are clearly VERY effective. I'm just not into that level of punishment;-)
