Well, this is embarrassing

[DocV]

HI George,

Yes, it looks like it would line up with the top of the barrel ramp if I was able to shove it that far into the barrel. None of the other cases from that lot show any signs of a bulge. It was likely some combination of overcharge and bullet setback rather than a support issue or bad brass. The pistol passes both the go and no-go gage tests. It looks good to go but I will test it with some factory rounds.

[DocV]

George,

I agree with your swaging concern and think that might have been a factor in my problem. I recently started using a Lyman M-die for my lead bullets. That die, and due diligence, seems to have cured a lot of my lead projectile loading concerns.

[wharvey]

Looks like some 9mm cases my daughter and I "enjoyed". A couple of times in an old Star M30 I use to have and one in my Shield. No damage to either gun but we had to fight flinching for a bit afterwards. I know there were no double, or over charges for that matter, due to using a single stage press and the way I charge the cases. (Put 50 primed cases in a loading block, charge, then look at the cases. Any difference in powder level is very easy to spot.)
Since it happened in two different guns all that was left was weak cases. These had been reloaded several times and I'd guess were at least 10 years old. I figured the brass was just fatigued beyond use. Did go on and shot them up. Not the smartest thing to do but also didn't bother picking up brass afterwards.

[DocV]

I load on a Rock Chucker in small batches just as you described. In addition to having had to fight a bit of flinch for a while, I also doubled up on the visual powder checks. In retrospect I doubt the case contributed much to my problem that I think was due to over crimping and set back. Overall a the incident made for a very educational experience.