Mossberg 510 youth issues

[mralberta]

I purchased a Mossberg 510 youth .410 pump for my 11 year old son. Cleaned the gun, took it out using 2.5" shells. The gun is really hard to cycle.

Load, shoot, pump.... and the action wont open, it takes extreme force to actually cycle the gun to chamber the next round. I have dissassembled , cleaned up again and the problem still persists. using 3" rounds it has the same problem.

My son cant get it to cycle and I struggle with it to.

Any suggestions? Anything to look for???

 

[B]

Rough chamber would be my guess. Any noticeable difference just pumping it dry vs fired or with cheap vs higher-end ammunition?

 

[mralberta]

Dry seems fine. It’s only when you chamber a round. I’ve tried high end slugs, 3” rounds, they are all the same.

 

[Suther]

Dry seems fine. It’s only when you chamber a round. I’ve tried high end slugs, 3” rounds, they are all the same.

What about cycling ammo, but not firing it? Does it cycle fine like it does while dry, or does it get stuck trying to eject an unfired cartridge?

 

[B]

Dry seems fine. It’s only when you chamber a round. I’ve tried high end slugs, 3” rounds, they are all the same.

Usually better ammo will produce a noticeable difference but if it's very rough it may be too far gone. An easy enough polish can fix it but it is hard to say that is your problem for sure.

 

[mralberta]

What about cycling ammo, but not firing it? Does it cycle fine like it does while dry, or does it get stuck trying to eject an unfired cartridge?

I haven’t tried that. But it feels like the spent shell is tight in the chamber causing a hard cycle? Is that possible?

 

[tigrr]

Take it apart and look into the chamber with a good flashlight. If there is no chamber roughness lube the rails and bolt to the extreme and try again.

 

[0faustus0]

If the gun is cycling fine without ammo .... and with ammo that has not been fired ... then it is likely a rough champer that needs polishing.

Use some very fine steel wool on a bore brush and with a drill ... lots of lube ... and polish the chamber.

I had to do this to a couple of my 870s ...

 

[Suther]

I haven’t tried that. But it feels like the spent shell is tight in the chamber causing a hard cycle? Is that possible?

Yeah, if the chamber is rough there can be a lot of friction between it and the plastic hull after firing.

 

[cosmic]

Yeah, if the chamber is rough there can be a lot of friction between it and the plastic hull after firing.

I think you mean the steel case head.

 

[mralberta]

Range report: Cycling unfired rounds through the gun with ease. Absolutely no resistance or binding. Fired rounds on the other hand are extremely hard to eject and cycle.

Any polishing tips? I have never done it

 

[0faustus0]

very fine steel wool wrapped around a bronze brush on a rod ... and a drill .... use lots of oil ...

Llink

 

[B]

Using a very fine polish will save a ton of time.

 

[doctor_meltdown]

I had a 500 that had the same issue. I had it fixed under warranty. It was the chamber as mentioned above.

 

[mralberta]

Problem resolved: The rounds i was using were short brass cases. They seemed to expand after firing causing the shell to get stuck in the chamber. I fired high brass through the gun and problem solved. It is hard to find a high brass round, Canadian Tire had them at $50 a box. I found Budget Shooting Supplies caries them at $34 a box.

 

[alpining]

Problem resolved: The rounds i was using were short brass cases. They seemed to expand after firing causing the shell to get stuck in the chamber. I fired high brass through the gun and problem solved....

Thanks for circling back, glad you got it working.

It should work properly with low brass shells, and polishing the chamber is the most likely solution for this. All cases expand during firing and then contract again after the chamber pressure drops, but fired hulls will still be larger than unfired. High brass hulls are generally higher quality (made with better material and higher tolerances), which is probably why your shotgun prefers them in its current state.

Rough chambers are probably the most common problem with new shotguns. You should be able to get it fixed under warranty as the poster above did, but it's not hard to DIY the fix yourself. But it is possible to ruin a barrel by removing too much material. Most guys probably use the bore brush method mentioned above, which is fine if you're careful and/or have a bit of mechanical background. There is a specialized tool made exactly for this job, it's not that expensive.