Broke my Mossberg 500

[essayons21]

I was out with some friends shooting Federal 3" 1.25 oz slugs blowing up milk jugs. Good fun, especially with my lightweight shotgun. A mix of about a dozen slugs and another dozen buck and birdshot before the malfunction occurred.

The gun wouldn't eject a 3" shell, as the bolt wouldn't travel fully to the rear. The slide still functioned, and it would probably cycle 2 3/4 shells, but not 3".

Took it home, cut and yanked the spent shell and broke the gun down. Found that the firing pin was jammed fully to the rear in the bolt, and had a hard time getting the bolt apart. After much cussing and hammering and a broken punch I managed to get the thing apart. The culprit was a sheared firing pin retaining pin. It appeared that the firing pin took a "C" shaped chunk out of the retaining pin, and that jammed everything up tight. I shoulda taken pictures, but its back together and working now, and its a pain to take apart.

Simple fix, I just rotated the pin 90 degrees and everything works fine now. I have ordered a replacement.

Coupla questions... has this happened to anyone before? This is my "tactical" home-defense and 3-gun shotgun, I have put about 2k rounds thru it, mostly bird and low-recoil buck and slug. I don't fire much in the way of heavy recoiling stuff, maybe only a half-dozen boxes total. The gun hasn't been abused in any way. Did I get a lemon or is this a design flaw, or is this a wear part that needs to be periodically replaced?

Comments or advice welcome.

The gun in question

 

[jlv08]

I have never heard of this happening to any Mossberg in my lifetime.
I've had several Mossie's and they all have been reliable as gravity.

Probably a defective pin as that kind of thing happens from time to time,

I would definitely replace the pin and then run her thru some shells.

If this is your HD weapon, you'll want to ensure that it'll bark when it's called upon!

 

[Taurus 617 CCW]

That's a new one on me. You may PM MountainBear as he is a Mossberg armorer and may be able to help you out a little more.

 

[DasFriek]

On a side note, What optic you have on it and how has it held up?
I put a SG specific under barrel laser/light combo on mine when i first bought it and it fell apart before i could empty the first tube.
I maybe have 200 rounds threw mine, But alot were 3" and some high powered 2 3/4" 00 buck and the gun has held up to the abuse well so far.

 

[RandKL]

Well, the obvious thing to ask would be "what forced the firing pin backward?" There's nothing on the gun that can do that. It can't happen by itself. That leads one to believe it was probably a defective shell/primer that blew backward with enough force to force the pin backward. Maybe a deep-seated primer on a shell that forced it back?

There's nothing on the gun that can cause that sort of prob, though. Has to be ammo.

rich

 

[essayons21]

I checked out the shell, and primer, nothing wrong with it. Also forgot to mention that the firing pin had also rotated about 30 degrees. From the shape of the chunk taken out of the retaining pin, I think the firing pin rotated before breaking the retaining pin.

When I get my replacement pin I will take everything apart and take pictures.

On a side note, What optic you have on it and how has it held up?
I put a SG specific under barrel laser/light combo on mine when i first bought it and it fell apart before i could empty the first tube.
I maybe have 200 rounds threw mine, But alot were 3" and some high powered 2 3/4" 00 buck and the gun has held up to the abuse well so far.

C-more Railway is the optic. http://www.cmore.com/railway.html#Anchor-rw2 It has held up very well to recoil. I used to use a chinese knock-off Aimpoint I got from e-bay which actually worked great and held up to recoil. I would recommend it if you are looking for a cheap red dot sight.

The light is a $17 Brinkman flashlight you can buy at Target. These things are amazing, I have quite a few Surefire's and this stacks right up there with them. Even survived a tour of Iraq with me... the other light I carried daily was a $130 Surefire Z2 Combatlight, and its bezel broke.

 

[AcceptableUserName]

not being the most tacticool guy in the world aside, the one thing I really DO like about your shotgun Essayons is the folding stock. I've been in the search for a quality, good-looking folder for my next shotgun.

what does the stock setup consist of? How sturdy does it feel to YOU? Could you see it functional in 20 years under constant use from the 12 gauge? Obviously a lot of the tube adaption stuff was meant for rifles, but if I could find the right setup that'd withstand the 12 gauge abuse call me intrigued.

 

[essayons21]

It actually is a fixed ACE skeleton stock on a ERGO AR-tube adapter. It is rock solid and I'm confident will last a lifetime. I'm not sure if Ergo is still selling these. Stay away from the other plastic adapters, they generally suck. Mesa Tactical sells a high quality aluminum adapter, but they are pricey.

Interesting you asked though, because I am planning on converting it to a folder, which will be pretty straightforward. ACE is pretty much the only game out there for this application. In addition to the ERGO adapter, it will involve a AR-15 compact receiver block and a folding or a push-button folding stock mechanism. Then you can add any of ACE's stocks. All of their products I have used are high-quality and pretty bombproof... they started out making stocks for AK's and FAL's.

 

[RandKL]

I checked out the shell, and primer, nothing wrong with it.

If it were a deep-seated primer that popped backward, it would be stopped by the bolt face and look pretty innocuous. Once again, there is nothing in the gun that can do that, so it had to be ammo related. Well, unless you have some of William Shatner's gremlins that run up, smack your gun around, and then disappear again, it has to be ammo related.

r