Mossberg 151M-B Doubling Problem

[Jocko]

Hi Folks -
Just have a question on my new to me beauty 151M-B. Was out to the range today getting in some practice and every time I loaded some more rounds in the magazine it would double on me. Only the first time I pulled the trigger after loading. The next rounds would fire OK after the first trigger pull. So then after trying a few different things I find it won't double as long as I pull the trigger on an empty chamber after all rounds are expended and let the hammer and trigger fall so to speak and then load some more rounds. As long as I load more bullets with it uncocked and then cock and charge the chamber it won't double. I also tried loading more rounds in after emptying the rifle, with the bolt having ejected the final case and cocking the rifle
then putting a few more rounds in and racking the bolt to put a round in the chamber it then doubles again.

Ever heard of this before ? Any and all help is appreciated.

Thank - you

[dave]

Seems odd but the first thing I would do is take the bolt apart and clean it, old dry grease/oil, unburnd powder, etc. made sure there are no burrs on firing pin that are making pin stick. There will be burrs as Moss parts were stamped and not polished off. Lay it on a flat surface with fine emory cloth and polish back and forth, both sides. Lightly grease with a GUN grease and reassemble. If you do not know or can not figure how bolt is removed and disasembled go to 'gun boards', Moss. forum, and get instruction and more advise on the problem. They love to help new guys out. It sounds like maybe a disconnect problem but that would be consitent without seeing it hard to say. Let us know what happens, don't just keep silent!

[CHW2021]

I am working from memory, so forgive me if I am wrong. I think that part of your problem may be spring tension feeding the next round hard enough to keep the bolt from fully cycling and allowing a slam fire. Additionally, some mossbergs have firing pin breakage, so that is also something to check. The guru is Vic at Havlin sales http://www.havlinsales.com/
Disassemble and clean before anything, soak and clean the bolt well.

Good luck.

[kcw]

I'd also start with a complete cleaning just to get things "back to basics', with everything moving the way it was designed to. I like to use automotive brake cleaner with the "straw" on the nozzle. If EVERYTHING in the action gets flushed out, looks good and is lightly re-oiled; and you still have problem, I'd look for a worn disconnector or weak disconnector spring. My guess would be however that a good cleaning will solve the problem.

[Jocko]

Guys -

Thanks for all the replies.

When I obtained the rifle I did a complete break down and cleaned everything.
So I know it is spic & span internally. Bolt was cleaned as well and firing pin looked A*O*K.

I do have an email in to the Havlin folks, we'll see what they say and I'll post it here.