View Full Version : 870 Express w/Knoxx Stock Issues

07-28-2008, 2:37 PM
Ever since I added the Knoxx specops stock on my 870 EM, I've been having problems ejecting spent shells. They would get lodged in the chamber requiring a strong/slow pull to eject it out. It happens about 50% of the time with buckshot/slugs. Maybe 5-10% with birdshot.

I believe its because of the suspension inside the stock partially racking the foreend during recoil. I was watching my buddy shoot a slug, right after he shot it, the empty hull was sitting partially extracted in the chamber.

Im wondering

1.Do I have a defective Knoxx Unit with weak springs?
2.Is there a problem with my shotgun and I should of purchased a Police model?
3.Do I have a problem with my form? Should I pull in with the pistol grip and push into the foreend?

Any feedback is appreciated. Thanks

07-28-2008, 2:44 PM
When's the last time you cleaned your gun? I don't believe the knoxx stock goes inside the receiver at all.

07-28-2008, 4:20 PM
No stock made for the 870 will cause shells to stick in the chamber. You need to polish the chamber or clean the chamber.


07-28-2008, 4:49 PM
I just put a Knoxx Specops stock on my Rem 870 Express Magnum. It took at least fifty rounds to get used to. Once I became familiar with it and found my groove, I was able to decide it was money well spent and I would keep that configuration. I have only shot 100-125 rounds through it with the new stock, and a huge variety of loads, shot/buck/slug/sabots, high brass and reduced recoil, 2&3/4" and 3", and not one failure of any kind.

Try shooting your 870 bench style. Rest the fore end on a bag and take a shot. Now inspect the gun--the action should be closed, and assuming proper form, the fore end shouldn't have moved rearward at all. Take the human element out of the shot as much as possible and examine the gun closely.

I have found this stock to be very helpful getting back on target quicker. A few more sessions at the range are needed to perfect my technique with this new configuration. Hope you figure it out--if you do, post the results!!!

07-28-2008, 6:34 PM
When's the last time you cleaned your gun? I don't believe the knoxx stock goes inside the receiver at all.

I clean it after every range trip. The shotgun is cleaned and lightly oiled before being put away. Its my home defense gun so I want to make sure it works.

I know the stock itself doesn't cause the hulls to get stuck in there. I meant the recoil suspension system with the combination of my form causes a partial racking of the foreend from the increased travel from stock, so when I go and rack it, it was already partially racked.

ex: If I were to shoot a single load of buckshot and then lay the shotgun on a table. You can see about 50% of the empty hull pulled out of the chamber. On a slug you might see the entire hull in the chamber. This is WITHOUT racking the foreend after the shot.

I am not sure if its because of the stock moving backwards and pulling the foreend/myself with it, followed with the rebound action of the stock pushing the gun forward again partially pumping the foreend

I guess the only way to find out is changing back to the factory stock and trying it again.

I might have to do an indoor range trip at LA Gun Club to find out.

07-28-2008, 6:42 PM
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Check out this video in slow motion. On my shotgun, right after the shot you can see a little movement on the forened. On his shotgun, the recoil does not partially extract a hull.

On my shotgun that little movement causes the shell to be partially extracted, and perhaps the rebound motion pushes the empty hull back in..so when I go to rack it again. It gets stuck?