ByzantineBonafide

I'm using a Lee single stage, just about everything I use is off the anniversary kit.

WacoKid, what is causing the rings? Any ideas?

Guy, I initially thought the same thing about the ring, but it's bigger than the bullet, though seats perfectly on the case. 4n2t0, yes, I do the plunk test for the OAL. I had these at 1.065, though I saw other recommendations for longer (1.1" or so) but I figured I should prioritize what passes the plunk test in my individual gun (correct me if I'm wrong). m700, thanks for the encouragement. It certainly can shake confidence, but you're right, it's overcome-able. M1A4, I think that procedure is going to be a must for me going forward. Eirc, no idea, actually. It's a good theory, but unfortunately I have no way to prove it.

HesedTech, I was trying to find a load to approximate store-bought defensive ammo that was cheaper to use for practice (I've heard you shouldn't put anything but factory in your carry gun).

Jack, I did actually try to seat a bullet with 8.6 in the case, and it did seat without spilling powder. Before, I was convinced that couldn't happen, and that I'd notice...and I solidly disproved that theory. Now that I've had a few hours to relax about it, yes, I DID get lucky. I contacted Sig and they are going to look it over and do all their tests, but think I'll just be out a little bit for an extractor replacement. I haven't looked at the other rounds yet, I was tempted to just chunk them and figure out what I need (new procedures and/or equipment) to make myself safer moving forward.

It is not stepped.

Eric, hard to say if it was a bigger boom, the surprise of the grips blowing out made me not notice. Memphis & Waco, there isn't enough on the case to read the headstamp. m700, the previous rounds were all fine, and I used a regular Lee single-stage. Not sure where the brass came from, something I nabbed on the range a few weeks ago I think.

Took the case out, here are the results. There was a weird ring left in the barrel.

I was working up a load for 124 gr Hornady XTP testing between 4-4.4 of Titegroup, and this happened on round #8 of the 4.3. As you can see the case is stuck in the chamber, and the bottom part of it is blown out. The pressure blew out the extractor and part of the grip. My best guess is that I loaded a double charge. I was super careful loading these, but human error is what it is. Thoughts? I'd like to make sure whatever happens doesn't happen again.