Is the bottom of the breechface on the bolt machined flat with the recess, or is the "feed lip" still on there? Hard to tell from the pic, but it looks intact. The FA piece has the lip there so the round will be pushed into the chamber in front of the FP. With the lip machined away the rear of the case slides up and jams against the bottom of the FP if it is jammed forward. With the lip, if the striker assembly is not held rearward the gun will fire when the bolt closes, without it it will jam during feeding.