wojtowicza

I have a Mossberg 500. When i have a shell in it and squeeze the trigger it doesn't go off the first time. It might take 2 or 3 squeezes till it fires. If i put a shell that has been already fired in it, it will fire everytime. Also, if i dry fire it, it will fire everytime. So i'm not sure when it will go off. It's a pump if that helps any. Can anyone give me some advice before i take it to the gunsmith?

johnch

Have you tore the bolt out and realy cleaned every thing .Take the bolt apart and clean everything ,the owners manual will tell you how
Take a tooth brush and clean the locking lug and bolt recess.
Litely oil and reasemble and try.
Is it happening if you slam the slide home ,close it easy or all the time ?
Is it happening with all shells ,1 brand or reloads ?
BEST BET it is dirty !

frizzellr

If that doesn't work contact Mossberg's customer service.

wojtowicza

i already took the bolt out and really cleaned it. i've tried all different ways of closing the slide, hard slow and easy. It's happening with all shells. i don't reload.

thanks

wojtowicza

could it be with the firing pin assembly maybe you think?

Rockfish1

if you didn't have the firing pin out you didn't clean the bolt... thats probably where the dirt is jamming things up......

driftrider

Sounds like it might be an inadequate headspace issue. What length shells are you using (2 3/4", 3", 3.5") and what length is your barrels chamber (it should be stamped on the barrel)? The reason I ask is that if you are trying to chamber a 3" shell in a 2.75" chamber (or a 3.5" in a 3" chamber), it's possible that the loaded shell is actually contacting the forcing cone and effectively headspacing the shell on the mouth instead the rim. If this is the case, the bolt may not be locking forward all the way and causeing the gun to fail to fire (as it's designed to do) until that shell is repeatedly crammed into the forcing cone enough to fully close the bolt. If this is the case you have a potentially deadly problem if you continue to use the longer shells because pressures can easily spike to dangerously high levels. You are effectively creating a partial barrel obstruction because the crimp cannot fully open to allow the wad and shot to pass without excessive constriction.

I'd strongly advise you to not shoot the gun until you are sure that the shells are at or below the chamber length stamped on the barrel. If you did shoot shells that are longer than the chamber, I'd strongly suggest that you take the gun to a gunsmith and have it checked for signs of excessive pressure to ensure it's still safe to fire.

Mike

bigbulls

Have you taken out the trigger assembly, completely disassembled it and cleaned inside the hammer spring housing and the spring itself and made sure the pin that the hammer rotates on is clean.

Also if it is a very old gun that has been shot a lot the hammer spring may have sim0ply weakened and need replacing. Springs will weaken over time and continued use.

Uhh, I don't get this. How can a shell fire if it's aready been fired?

9 times out of 10 it's a very dirty gun.

driftrider

I took when he says "fired" to mean than the hammer falls when the trigger is pulled whether the gun actually discharges or not.

I also think that if he's shooting a shell that is too long for the chamber, it wouldn't chamber easily, but could still chamber when forced depending on the length and pitch of the forcing cone, when loaded because it'd be difficult to squeeze the front of the shell into the forcing cone with the shell crimped on a shot charge. But one the shell was fired the crimp would be open and there would be no shot inside to prevent it from easily squeezing into the forcing cone, thus allowing it to completely chamber with ease and allow the hammer to drop every time when the trigger is pulled.

Mike

wojtowicza

my barrel can take 2-3/4 and 3 inch shells. I was using 2-3/4 shells.

what i meant by "shells already fired" is, Say i shot a round off. Now i take that spent shell and just put it in the chamber again just to see if i can squeeze the trigger on it or not. Everytime i will be able to squeeze the trigger. so the only differnce is the primer has already been hit with the firing pin. it never hangs up. it only seems the problem happens with a new shell.