• Mossberg Owners is in the process of upgrading the software. Please bear with us while we transition to the new look and new upgraded software.

can't pull pump back to eject expended shell.


Copper BB
I bought a Maverick 88 lat July and never fired it until today. I have filled the mag tube and cycled the rounds through it. But today I fired one round. I tried to eject the expended shell but the pump won't come back and the action lock is in the depressed position. There are 5 rounds in the mag tube.
It's my first shotgun so I don't know alot about it.
Can someone give me a clue. Thanks.
Couple of questions

Is your forearm assembly locked solid or can it be moved to the fully closed (forward) position?

Do the action bars seem to be intact?

Is the shell lifter positioned fully up and intact on both sides?

Here's a link to a schematic. If you locate item 10, the cartridge interrupter you will see it holds the live shells in the magazine. If you push it on the forward end each shell will released out of the magazine tube so you can "safe" the gun.


Hard to diagnose the problem given the limited information provided. Guess the final question is did you take the gun apart and check and clean the components before firing it?

Please provide detailed info and if available pictures of assembly from loading port.

The gun is now "safed".
The forearm assembly is fully forward and locked. I cannot open it to eject shell. The button to allow forearm to open is fully depressed and stuck.
I bought this gun last July at a pawn shop and just today got a chance to fire it. I loaded Remington Nitro Mag 3 inch #6. Maybe something is worn out.
Whatever it is, I can't pump it back to eject or load another round and the lock release button is fully depressed and stuck.
This is after firing one round.
I took it apart a couple of times and cleaned it right after I bought it.
Last edited:
Elmer, fellmann and I think alike. Inspect both sides of the receiver to see if the pins and screws are fully seated snd flush in their respective holes. Also inspect the internal parts by looking up in the loading port.

I suspect you have some part (lifter, cartridge stop or interrupter) out of place or the screw holding the ejector has loosened. About the only other thing might be one of the action bars is misaligned where connected to the bolt assembly.

Unfortuantly, with the forearm assembly locked completely forward you simply can't remove the barrel because the bolt is in lockup nor can't you use a wooden dowel knock the spent shell casing back.

If none of the above is obvious I'd remove the trigger group. The most rearward pin in receiver holds the trigger group in place. Pushing it out should allow the assembly to rotate out. Once out see if the forearm will move. If it will cycle inspect the trigger group and release. If the forearm will not move inspect the internals through the opening where the trigger assembly was.

Bottomline - very likely you have a misaligned part. Before shooting again strip the gun and inspect everything. Given it was a used gun and I'm assuming you didn't strip, inspect and/or clean it. The stoppage may also be from debris or pieces of old shell casing brass lodged in the bolt assembly.

Don't give up. I'm sure it's simple. Let us know what you find.

If your having trouble understanding the directions there are detailed disassembly videos on YouTube.

Have you tried to depress the slide lock release and pull the slide back simultaneously?

I know, that may seem like a stupid question, but I had to ask.

The reason I asked is if you pull the trigger when shooting, the slide/bolt will unlock and be able to move rearward normally.

But, if you push it back forward under recoil and it locks back up again without fully being pulled to the rear, you'll need to depress the stop again before it'll be able to be pulled back.

That may not be the answer to your problem, but it is one thing that maybe should be checked.
I got it taken apart finally after taking trigger housing out. Then i took barrel off. The expended round was stuck to to bolt but I got it off. I am now cleaning all parts and will reassemble.
Could it be that some part is worn and let it get jammed up like that? Could it be the ammo? This is my first shotgun so still, I'm clueless.
The action lock release button was stuck fully depressed but came back up after I got it apart.
I do appreciate the replies.
I bought this gun for home defence and considering the evil times, one shot may not be enough.
Congrats Elmer!

Assume once you removed the trigger assembly it freeded up the action?

If all the internal parts are fine including the ejector and bolt face I'd take a close look at the trigger assembly to see if the slide release is working fine and not sticking.

Then run the action back and forth many times to make sure it's functioning correctly. Might try a second brand of shells but doubt that was the cause.

Again, congrats and we've been remiss in not welcoming you to the forum already.

Lots of great folks here with decades of experience who are always willing to help!

Well, after fumbling with the bolt for an hour, I finally got it back together again. I cycled 5 shells through to make sure that worked. It seems like it's working right. The test will be when I fire it again. I don't know when that'll be. I live in town and I snuck that one shot off in my back yard while my neighbors were shooting fireworks and the report blended in.
My thanks to Ernst, John A and fellmann for the replies. If it jams again, I'll be back.
Welcome Elmerfudd!
You have an interesting issue that may take some more investigation. Since you didn’t find any obvious issues when you disassembled your 88 you may not be out of the woods yet. It’s a used firearm so who knows what went on with the previous owner(s).
Without any live shells in or near the gun can you dry fire it? Not just once but several times. If the gun won’t do this several times then you still have a problem.
Please keep us informed once you get a chance to live fire the gun again. I’d suggest just putting one round in the magazine. Cycle the fore end to load the shell and close the action. Make sure you have eye and ear protection on as well. Switch off the safety and with the muzzle pointed in a safe direction pull the trigger. If it discharges you should be able to cycle the action to eject the spent shell. If this works then load 2 more in the magazine and see if the gun behaves well with 2 live shells.
I dry fired it 4 or 5 times. The "click" didn't sound real "crisp" (for lack of a better word).
I live inside city limits and have no vehicle to go anyplace that i can fire it but will try to catch ride this week if I can find place to go.
On the bolt, there's a part that pushes down and springs back up (not sure of nomenclature of part), that sticks when depressed. It springs back up pretty easily if pushed back up from underneath. I used WD40 and oil to clean the bolt but it still sticks. I also had a hard time getting bolt in. It didn't seem to sit in there flat and straight. I had to push on it to get the elevator (?) in. But after getting it back together, it seemed to cycle the shells ok.
I'll post again as soon as I can go fire it again.
Agree John about the video's beginning, but this guy does a reasonable job of detailing how the shotgun's action works. Plus looking at his earlier videos gives a new user a fairly comprehensive understanding of how pump shotguns work and design differences between manufactures.

I've found the Mossberg's lockup mechanism is not understood by many folks especially those who critize the Mossberg's aluminum receiver as not bring strong enough. Just tells you they don't understand the lockup mechanism.

Plus many seem afraid to take the trigger assembly apart. It's actually quite simple once you understand how it functions with the most difficult part the reinstalling of the sear but using a couple of pin punches is all you really need.


He said "if it jams again, I'll be back," plus he does not have a car to get around. Then silence for ten days. I dunno if he fixed his problem, or just moved on.

Perhaps he is still looking for a ride so he can go somewhere.

Last edited: