What happened here?

[Liftrat]

Not sure if this should go here or in the Ammo section, so Mods please feel free to move it if need be.

Being an inveterate brass hound, I picked these up at my local range a while ago. While I've seen pierced primers, and flattened primers, and all manner of weird fired brass, I've never come across primers like this before. Anyone have any idea what happened here? My only guess is that perhaps excessive headspace caused the case to slam back against the breach, but that doesn't seem quite right. And the Federal case with the protruding lip has me stumped.

 

[ReloadforFun]

While I don't know the gun they were fired in, in a 1911 it would ake me think the firing pin spring was weak and allowed the firing pin indent to flow back into the firing pin tunnel. Then, as the barrel ramped down it sheared the now protruding firing pin indent.

 

[Liftrat]

Yep, that makes sense. Or the FP hole was too big. Thanks for the reply; once I got the mental image it all came together.