Sharp *outwards* bulges in case?

[twarr1]

I came across this case while tumbling a lot of brass. It has 2 sharp outward bulges. I can't figure out what caused this. And to be honest, I'm not 100% sure if it is one of mine or a range pickup one of my grandsons picked up mistakenly. Regardless, I'm curious how this could've happened.
Anyone have any insights?

 

[milsurpguy]

Maybe the shell had a stainless steel pin in there when it was fired.
That's kind of what it looks like but doesn't seem like it would leave that big of a dent.

 

[MEHavey]

Whatever caused it, it happened after it was fired.
(Chamber would never have allowed such protrusion).

Someone stuck a flat-bladed screwdriver in the case mouth and pried.....




.

 

[jmorris]

Whatever caused it, it happened after it was fired.
(Chamber would never have allowed such protrusion).

Unless there is an inclusion in the chamber, but then it would have a pretty heave rub mark once ejected. I agree with “after”.

 

[Goneshoot'n]

+1 on the “after fired”. Even with an inclusion in the chamber the bulge would have been flattened out on its way out of the chamber

 

[twarr1]

I'm also inclined to think it happened *after* firing. But someone must've done it intentionally.