weirdharold

I recently bought a FM 9.25" upper with a FM pistol lower. I removed the pistol buffer tube and replaced it with a mil-spec carbine tube(i.e. a SBR). I used the buffer and spring that came with the pistol in the carbine tube. The rifle has run perfectly with approx 1000 rounds of many types of ammo. The problem is the firing pin is dimpling the primers when the action is closed. Same problem with many brands of ammo and reloads. I'm worried about a slam fire. I have tried new factory firing pin and firing pin spring with same results. My question is: Do think that using the pistol buffer and spring as supplied by FM in the pistol in the carbine tube is causing the bolt to slam shut with too much force and causing the firing pin to dimple the primer? Anyone else have similar problems or any ideas? Thanks Rich

jersey, Unfortunately I just bought 10000 Federal small pistol primers for my handguns.

I forgot to mention that this is a 9mm PCC and the only thing keeping the firing pin away from the primer under these conditions is the firing pin spring. Thanks for the comments guys.

dauntedfuture, When the bolt is manually released with a cartridge in the chamber, the firing pin will "dimple" the primer. The hammer is never released.

I recently started shooting a FM Products SBR which has complete FM upper and lower. The problem is that the firing pin will strike the primer when the bolt is released. So far no slam fires, but this makes me very nervous. I stretched the firing pin spring which helped a little, but the primer strikes still occur. Has anyone had similar problems? Can I purchase a stiffer spring? If so where? I really like the rifle. It will run any ammo at 100%, but I am concerned about this issue.

I have two Gen 4 Glocks, a G35 and a G34. The G35 slide has been milled to accept a RMR sight. My question is: can I put the 9mm barrel and recoil spring from the G34 into the G35 slide and shoot it on the G34 frame with 9mm mags? Thanks for the info!