Help: 870 Police hanging after firing

North of 7 said:
Youtube the issue, pretty common. Basically, it boils down to the single extractor and the ring found on the barrel near cartridge rim, side opposite of the extractor (also rough chambers). When the extractor pulls on the side of the rim, it forces the other side into the groove and locks up the action. you can dry fire all day and never have the issue, seems to only happen when fired.

I took a dremel and smoothed out the area, as per youtube vid, as well as polished the chamber and ive never had the issue again.

North
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Not common at all on police models which he says this it just the cheaper express etc versions and never seen on pre mid 80's 870's
 
Ithaca IIRC, experimented with single extractor once. Was unreliable. Back to two extractors.

1974ish(?) Actually on 2nd thought it was shell stop mod that didn't work out.....not sure on year single extractor design.
 
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I got this in a pm and they wanted me to post it. They say it helped them and came from a US site

First:
#### the gun, look at the slide release finger tab on the left front of the trigger group.
Pull the trigger and watch the tab. It should snap upward when the trigger is pulled. Check to see if it moves freely and fully up into the group when the trigger is pulled.

Field strip the gun, (barrel off, trigger guard off, bolt out).

Check:
The top rear edge of the bolt's locking lug for burrs.
The rear edge of the locking recess in the barrel extension for burrs.
The left slide bar on the extreme rear for burrs on the beveled (sloped) end.
The bolt lock bar front end for burrs. (This is the bolt release/bolt lock lever on the left side of the trigger group.
The bolt lock/release for free movement up and down.

Any burrs, galling, or damage to any of those areas can cause jamming.

Burrs or machining roughness on the lock lug or the lock recess in the barrel are bad about causing the bolt to stick. Burrs are common on the Express.

The gun locks the bolt shut by the lock/release moving up until the front end prevents the left slide bar from moving back to unlock the gun.
The front end of the lock/release has to slide down the sloped end of the left side slide bar.
Any roughness on either surface may prevent the lock/release from moving down far enough to allow the slide to move backward.

The bolt lock/release in the trigger group must move up and down freely, or the gun won't unlock.
 
This issue is a combination of excessive operator induced rearward pressure of the forend and action bar lock mating surface machining. Sharp edges. REM assumes it will work itself in after much shooting. These surfaces will eventually wear for a smoother function with use, but keep in mind excessive rearward pressure on the forend during firing causes more damage than the speed gained cycling the action.
Recommend honing these surfaces for a smoother function and not applying so much rearward pressure with the forend.
There’s a hack people have used changing the angle of the mating surface on the action bar lock for faster/smoother unlocking, but I don’t think that’s wise.
Sometimes the action bar spring is an issue as well, but doubtful on a new gun.
 
Ok, so over the week end I had a better look at that gun.

First I tried to reproduce my problem by sticking a dowel down the barrel and by putting heavy pressure on that dowel while dry firing the gun with a dummy round. And I could not reproduce the issue. The gun would release the action bars right after pulling the trigger .... So, it seems the problem really only manifests itself under life fire recoil.

Then I compared the internals of this gun to another 870 that I have and which works fine. I couldn’t find any “significant” differences … However, I realized that some of the surfaces related to locking the bolt in place and locking the action bars were not polished and a bit rough to the touch.

So, I took the dremel tool out and some green polishing paste and I polished the mating surfaces in two areas ….

a.) the rear face of the bolt's locking lug and the locking recess in the barrel extension, and
b.) the rear end of the left action bar and action bar lock and where they meet.

I polished those surfaces the best I could.

I now need to test fire the gun again and see if this made a difference. Hopefully I will get out to the range next week end … and I will see ….

And if this did not work, then I will have to swap out the internals with the ones from my other 870s and test fire different combinations and to try to narrow down the problem to a specific part.


Thanks for the help everyone! Much appreciated.
 
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Just a thought; I wonder if it it has something to do with the extension not tightening the barrel enough into the receiver.
 
Indeed every new barrel I’ve come across had some sharp edges in the barrel lockup recess. It gets somewhat burred with use as well. I’ve found burrs in the extractor notch too.
Let us know how it goes. Always interested.
 
Brutus said:
Sometimes a certain name brand can contribute or actually be the root cause of a stuck bolt.
Folks, I found out that Challenger shotshell brand can cause exactly this jamming after live fire.
Switched to Winchester and Federal, problem solved itself.

Info.
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My HP9 with 870 parts cycles challenger shells fine and dont need more then 2 fingers to open the action. Telling me Chinese did it better then American?
 
OkayShooter said:
My HP9 with 870 parts cycles challenger shells fine and dont need more then 2 fingers to open the action. Telling me Chinese did it better then American?
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For how long and how many shells fired and ZERO true 870 parts beat
72 years and some with 100,000 rounds and never touched like some of my wingmasters :) and then I will say they are better
 
Brutus said:
Challenger field shells versus target shells.
A world of difference.
Those that shoot trap skeet clays regular basis do not consider this name brand for competition.
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These were the green hulls.

3macs1 said:
For how long and how many shells fired
72 years and some with 100,000 rounds and never touched like some of my wingmasters :)
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Umm couple hundred. Just amazes me how a company that been making the same shotgun for many decades, are making them worst.
 
OkayShooter said:
These were the green hulls.



Umm couple hundred. Just amazes me how a company that been making the same shotgun for many decades, are making them worst.
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What company they went bankrupt
It is simple people would not pay to have the quality of a wingmaster any more with so many other crap cheap shot guns out there they had to compete against so they changed the design in 87 and it started to slide then
Don't get me wrong nothing wrong with an express when it works and what you pay for one and most do just fine but they will never be a wingmaster and anyone that owns a vintage wingmaster knows exactly what I mean.

Cheers
 
The culprit is likely the locking block being incorrectly fitting when fired it should fall straight down it is hanging up on something.
Likely in the Recess in the bbl it fits to tight and does not fall freely .
 
Low metal shells tend to seize up inside 870s after firing. I have encountered several 870 Express models that would seize up whenever I tried cycling the cheap loads with low metal bases. I have a couple Express models that will only cycle high metal shells. That said, my older Wingmaster will cycle anything I fired.
 
OP covered cheap shells in his original post..... it should be pretty easy to look for burrs and even easier to push forward with the weak hand while firing.... :)

Maybe the OP will update us with what he has tried and has not bothered to try... and hopefully he's got it working!
 
0faustus0 said:
Ok, so over the week end I had a better look at that gun.

First I tried to reproduce my problem by sticking a dowel down the barrel and by putting heavy pressure on that dowel while dry firing the gun with a dummy round. And I could not reproduce the issue. The gun would release the action bars right after pulling the trigger .... So, it seems the problem really only manifests itself under life fire recoil.

Then I compared the internals of this gun to another 870 that I have and which works fine. I couldn’t find any “significant” differences … However, I realized that some of the surfaces related to locking the bolt in place and locking the action bars were not polished and a bit rough to the touch.

So, I took the dremel tool out and some green polishing paste and I polished the mating surfaces in two areas ….

a.) the rear face of the bolt's locking lug and the locking recess in the barrel extension, and
b.) the rear end of the left action bar and action bar lock and where they meet.

I polished those surfaces the best I could.

I now need to test fire the gun again and see if this made a difference. Hopefully I will get out to the range next week end … and I will see ….

And if this did not work, then I will have to swap out the internals with the ones from my other 870s and test fire different combinations and to try to narrow down the problem to a specific part.


Thanks for the help everyone! Much appreciated.
Click to expand...


So, I was able to get out to the range today … and I test fired that gun.

All is working fine now …. Yippiiiiiiii …. !!! She is cycling beautifully!

The action bars are now releasing right after firing …. and as it should be ….

No more hang up!

Polishing those areas was all it took to resolve this issue.

I believe it was the action bar lock that had a “rough” unpolished surface mating with a rough surface of the rear end of the left action bar …. and this prevented the action bar lock to drop down upon firing ….

Again, thanks for the help everyone!!

Problem is solved thanks to the CGN community!
 
Glad it worked out for you. Thanks for the follow up info. Hopefully this tread will be helpful to others in the future.
 
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