AMERC 45acp brass
I read about reloaders on the mainland tossing out AMERC headstamp brass.
My coworker found some at the range here and picked them up.
They appear to be perfectly normal but when you reload them, they don't chamber.
Top photo is WCC brass which was reloaded about 3 times.
Bottom photo is an AMERC once-fired shell.
The load was a 230 gr. polymer coated round nose.

It seems like the web portion is bloated and an ordinary (dillon) sizer die can't squeeze it down.
Perhaps a LEE FCD would bring it back down but I have not tried it yet.
The gauge pictured here is a MIDWAY chamber gauge.
I suspect for most guns, it will work ok. Normal pistol barrels aren't cut so tight.