i own a colt Automatic .25 that i inherited. the gun was made in the early 70s i believe 72 or 73 and it was a daily ccw of my grandparent. i recently took it to the range and i noticed it would misfire once or twice every couple MAGS. the ammo was new. after pulling the trigger nothing would happen, i would extract the round and notice an indentation on the primer (if thats what its called) then cock it again and it would fire fine. i was wondering if this is a problem with the firing pin or some other part of the gun or the ammunition being a dud. and if its the ammunition, is it common to get 4 or 5 duds in one box?