just got done resing and priming some black hills match once fired brass.when i started priming i found that a few of the brass have and indeted ring around the primer pocket and will not accept a new primer to make sure wasn't something i done i checked some fired brass i hadn't cleaned yet only thing done to them was deprimed with rcbs depriming die. found a few in those too only 7 out of the hundred i worked were fouled up. have you guys seeen this before, a flaw from the factory or did i do something im not aware of. thax for any help and advice