I've always had revolvers growing up. Decided to get an M9 Beretta and give it a whirl. Shot it for the first time today and enjoyed it. Disassembled it for cleaning and when I went to reassemble it, I am finding the flat head of the hammer pin stops the slide from moving all the way back to the lock position. I've watched videos and read posts on disassembling and reassembling which seems pretty straight forward. Any help from you Beretta veterans would be appreciated.