Mossberg pump question - light primer strike

[Charlie]

Turkey season opened Saturday, and one of the fellows hunting the farm was shooting some model of a Mossberg pump. He drew down on a longboard, pulled the trigger, and heard a click but no boom. He gently shucked in another shell and had the same thing happen a second time. The turkey left unharmed. Both shells had a slight dimple where the firing pin struck them without enough force to fire the shell. He later shucked in a shell with the normal amount of gusto and had the gun fire normally. I am happy to report that both he and the fellow with him got birds.

My question is why the shotgun would even allow the hammer to drop if the action was not fully closed and ready to fire. He had closed the action on both of the failed rounds rather gently to reduce noise. I suppose he did not get the action 100% closed. Is this a common thing with Mossberg shotguns? I have very little experience with them. Is it a design flaw that allows this to happen?

 

[Bailey Boat]

Have him check the firing pin channel in the breach block, it could be dirty and gummed up, clean as needed.
Also, most pump guns (870's, 500's 590's) aren't meant to be babied when operated. They have a lot of things going on during the pump stroke and without enough inertia being applied it may fail to complete all of the required actions. I always teach people to pump that bitch like you're MAD at it.....

 

[Get Off My Lawn]

It happened to my son’s mossberg , twice. Both times it took their warranty dept >4 months to replace the bolt assembly. The steel was soft enough it deformed under l use with bird shot.
The mossberg was sold then replaced with a Benelli Nova that’s run for years without a hiccup.

 

[BowWow]

My question is why the shotgun would even allow the hammer to drop if the action was not fully closed and ready to fire. He had closed the action on both of the failed rounds rather gently to reduce noise. I suppose he did not get the action 100% closed. Is this a common thing with Mossberg shotguns? I have very little experience with them. Is it a design flaw that allows this to happen?

Remove the barrel from the action and be sure everything is clean, no grit, burrs, etc and reassemble. Sometimes...…… especially if the gun is fairly new, you do have to cycle the action with more force than normal.

 

[Charlie]

I suppose I am surprised that the hammer could be allowed to fall at all until the action is fully closed. The pumps I shoot are M12 and M97 Winchesters, 870 Remingtons, and a M37 Ithaca and have never noticed this problem with any of them. Perhaps that is because I do as BB suggested and work the actions with vigor. I had a Mossberg but gave it to a friend before I had a chance to shoot it very much.