Quoted:
Just received a new BCG for one of my PSA 10's.  Took it to the range today.   Took two shots and experienced failure to eject for both shots.  I loaded each round individually.  In each case the bolt locked back with the empty hanging out the side.   Took the  BCG out to inspect it, when the firing pin retaining pin dropped off and bounced to who knows where.   The firing pin retaining pin was loose when I got it and I should have known better.