Beretta 390 misfires

[fecmech]

Gentlemen--I have a Beretta 390 12 ga that I shoot Sporting with and have a problem. When I shoot Estate shells (they have hard primers) I will get 2 or 3 out of 100 that won't fire on the first hit. A lot of other fellows I shoot with use the Estates in their 390's and 391's with no problem. I have changed out the hammer spring twice, the firing pin and the firing pin rebound spring with no help. Aside from not shooting Estates any ideas what might be wrong? Everything is clean, no burrs on the bolt or locking lug. Nick

 

[HSMITH]

Is the firing pin, spring and channel clean and DRY? If not make it so. Also spray out the trigger group with gunscrubber and then VERY lightly oil it, not enough to lube it though as you are just preventing rust.

 

[fecmech]

HS--All that has been done, trigger group degreased and blown out with compressed air along with the bolt assy. All were then lighly oiled and excess oil blown off with compressed air. If I don't come up with any ideas here I'm going to see if I can get one of the guys at the range to swap parts with me and see if I can nail it down that way. Figured I'd swap out a trigger group first and if no help try a bolt assy next. Nick