I'm building a gen 3 g21(45acp) upper and the fireing pin safety plunger dose not fit in the hole. The fireing pin safety plunger-(.263) and The Hole-(.260) are roughly the same diameter. As both parts are manufactured by two separate companies (not glock). I'm trying to figure out what part is out of spec. Can someone give me the correct diameter for both parts. I cant find it any where thank you for the help.