The rim on the 54s sticks out and the 51s are straight. Do not think it would eject properly or reliably. Just picked up a sporterized Nagant and he tossed in a box of 80 grain ammo. I thought I had bought some weird caliber but when I tried the standard 54Rs in it they chambered perfectly. Had never seen any 80 gn 54 ammo before. Like another said--do not think I want to be behind the rifle when the striker falls--lol.