DIY action job?

[Jpsmith1]

Remington 870, Newer model, not the old Wingmaster like mine is. Bought for my son who doesn't hunt anymore and I'm appropriating it because it's a 3" chamber and mine isn't.

This is, hands down, the worst running shotgun I have ever laid hands on. Action is rough and sticky and just unpleasant to run.

I've got a plan to coat the action bars in valve lapping compound, run the slide a couple thousand times over a week or so, hose the gun out with degreaser and oil it up.

Does anyone see a problem?

 

[Stearinlys]

Well, like we say here in the shop, "Only one way to find out!"

But by the sounds of it, it can't really get any worse. Actions get lapped all the time, give her a shot! (No pun intended)

Also, may not be related at all, but was it cleaned right off the get go? I remember hearing some guys complaining that the Mossbergs would be similar, and it was the anti-corrosion crap they put in from factory that was gumming everything up. Once it was taken apart and cleaned really well, then re-oiled it worked fine after that.

 

[jjohnsonElknewbie]

On the Mossberg 500s I've worked on for family and friends, some polishing of the internals including the pump arms would likely improve smoothness. From the factory most parts have sharp edges that tend to bind and snag. I'm guessing the newer and more affordable 870s are the same. I'd say execute your plan and then disassemble the action completely and look for and address any other sharp or binding areas.

My late 60s Ithaca 37 is by far the smoothest running pump I've ever used. This was true of every Ithaca 37 my family owned in both 12 and 20. When I hit the pump advance button on the front of the trigger guard it actually drops on it's own an inch or so. They're absolute butter.

 

[Jpsmith1]

On the Mossberg 500s I've worked on for family and friends, some polishing of the internals including the pump arms would likely improve smoothness. From the factory most parts have sharp edges that tend to bind and snag. I'm guessing the newer and more affordable 870s are the same. I'd say execute your plan and then disassemble the action completely and look for and address any other sharp or binding areas.

My late 60s Ithaca 37 is by far the smoothest running pump I've ever used. This was true of every Ithaca 37 my family owned in both 12 and 20. When I hit the pump advance button on the front of the trigger guard it actually drops on it's own an inch or so. They're absolute butter.

I have an older Wingmaster and it's just super smooth.

Well, like we say here in the shop, "Only one way to find out!"

But by the sounds of it, it can't really get any worse. Actions get lapped all the time, give her a shot! (No pun intended)

Also, may not be related at all, but was it cleaned right off the get go? I remember hearing some guys complaining that the Mossbergs would be similar, and it was the anti-corrosion crap they put in from factory that was gumming everything up. Once it was taken apart and cleaned really well, then re-oiled it worked fine after that.

It may not have been cleaned right at the get go, but I have subsequently scrubbed the gun down and lightly oiled all the moving parts.


Thank you

 

[Wrench]

I'd start by exercising it and looking for where it's dragging. You can address those areas individually. Lapping compound is not the most fun to clean out.

 

[Macintosh]

I got sick of how fugly mine was so I used a spare piecce of walnut I had lying around, and voila, I now own the worlds nicest 870 express. I worked on a couple others too. I will say that after running mine a couple thousand times it smoothed out a LOT. It’ll never be model 12 smooth, but slick it up and the ones Ive used have all run reliably.

 

[100percent]

I sandblasted the interior bolt housing, slides and bolt on one of mine out of sheer curiosity, it worked like a charm! Valve lapping compound would be a great alternative. Go for it!

 

[jjohnsonElknewbie]

I have an older Wingmaster and it's just super smooth.

Agree, they're very nice pump guns, and the brand new ones look very nice as well. I haven't handled one, but they have the deep bluing and nice wood of the pre-1990s models. Local gun store guys say they're run very well.

 

[jjohnsonElknewbie]

A lot of guys use J&B Bore paste to smooth out the Ruger American action to eliminate the "zipper" sound. There are several youtube videos on this, and they're basically doing same thing you're trying to achieve. They cover the bolt and inside of the action with the stuff and run the action hundreds of times, and it eventually polishes both surfaces to a smooth surface.