While working up a load for my new rifle I had a piece of brass stick in the chamber and it was really hard to open the bolt. I insected the brass and found what you hopefully see in the pics. It looks as though the bottom shoulder deformed while firing or was deformed prior to firing. The load was 42gr of H4350 under a 140gr VLD. The brass is new Winchester 7mm-08 necked down in a RCBS FL sizer die.