870 Magazine Cap loosens up while shooting!

[marklbucla]

After my last range trip, I noticed that the magazine cap was really loose after shooting around 75 rounds. I tightened it up as good as I could this time around, but it still loosened up after only 25 rounds. Any suggestions as to how to prevent this from happening again? Is it really dangerous?

Oh, forgot to mention that I dremeled down the little dimple in the mag to fit an extension before.

 

[Oldnamvet]

I knew a guy who had a problem with it and he just wrapped teflon plumbers tape around the threads before he screwed it on. Didn't loosen up after that. Of course, anytime he took it off he had to clean out the old tape and use new.

 

[richardschennberg]

I usually check mine before each day of shooting. As far as I know, the only hazard is the possiblity of launching the magazine spring and perhaps a couple other parts. Since this could happen when the gun is unloaded and everyone may not have eye protection on at that time, it is at least a minor safety issue. Some Remington 870s have a couple dimples that prevent the spring from exiting at high speed; new Benellis have a tight-fitting spring retainer in addition to the cap. In cases like this, the cap is only necessary for cosmetics and to retain a magazine plug, if installed.
Richard
Schennberg.com

 

[vesmcd]

Make sure you still have the little detent ball in the barrel collar where the mag cap screws on.

 

[dfariswheel]

Since you removed the dimples, there is nothing to keep the Express plastic magazine spring retainer in place, and that retainer also acted as a friction device to keep the magazine cap from unscrewing.

You have two choices:
1. Use a pair of padded pliers to tighten the magazine cap down tight, and keep an eye on it to be sure it doesn't come loose.
Be careful not to tighten the cap TOO tight, since this can cause feed problems.

2. Buy a new Wingmaster or Police barrel with the spring-loaded detent in the front face of the barrel support ring.
You will also need to buy a Wingmaster or Police Old Style magazine cap, and magazine spring retainer cup-washer.

If you go the new barrel route, the Express magazine cap WILL NOT work.

 

[richardschennberg]

After reinstalling a spring, you have to push the follower a couple inches into the tube several times to untwist the spring. A compressed spring has some rotational tension, and if you don't untwist it before loading shells the rotation effect might be enought to untwist your magazine cap.
Richard
Schennberg.com

 

[marklbucla]

Can I expect the same problem with a choate mag extension in place of the mag cap? I had one on there, but the barrel clamp kept coming off so I removed the extension. I kept tightening the clamp but the threads have all worn off on its bolt.

 

[c_yeager]

Make sure you still have the little detent ball in the barrel collar where the mag cap screws on.

He doesnt have the ball detent, thats what the dimples are for.

 

[dfariswheel]

"Can I expect the same problem with a choate mag extension in place of the mag cap?"

You shouldn't have any problems with a Choate.

If you're having problems getting the clamp tight enough, I recommend replacing the stock clamp with Uncle Mike's copy of the Remington Police magazine clamp.

These provide more clamping power:
http://www.michaelsoforegon.com/adt...y=1465723&subcatky1=4548843&subcatky2=2000180

If you use a good clamp, it will prevent the extension from unscrewing, as well as protecting the extension from being knocked off by a bump.

 

[Onmilo]

This has been a problem with Remington guns since Remington started using magazine caps.
A single wrap of Electricians tape around the magazine tube threads usually takes care of the problem.

 

[marklbucla]

Will a Wilson Combat bottom Sling adapter work too? I saw a pic of one on a Gunbroker ad and it looked like it had a sort of ball in it.

 

[Gun Geezer]

Wingmaster?

I have seen a Remington 11-87 on which the internal threads of the cap were 75% stripped out. With each shot the barrel got looser and looser. The barrel can fly off with the forestock if the cap does not do its job so, yes I would say this could be dangerous.

My 870 is a Wingmaster. This model has the detent in the barrel collar and mating female dimples in the cap. If you took a drimel and boogered up the detent or dimples then that could be THE problem. The thread tape could work but he perma-fix is to return the detents and dimples to as designed. A new cap is only $13 from Remington. You can buy new detents but they are a booger to install.

good luck.

 

[bcochran]

cap

Have had the problem for years. I tighten as I go along. If I forget, well, the internals sometimes come out.

 

[Bix]

marklbucla - as others have suggested, in removing the "dimples' in the magazine tube, you eliminated a component of the system that the Express guns use to keep the mag cap in place.

The sling adaptor will not solve this problem.

I've been looking for a cheap fix for the "dremmeled Express" problem and tried the detent sling adaptor myself.

Unfortunately, the detent ball in the sling plate is not spring loaded. It just floats. So, you can't get it to line up with a dimple as you tighten the mag cap (it just backs up against the unyielding barrel ring). I tried sandwiching some foam between the detent ball and the barrel ring to give it some "spring," but this did not work either. If you have a solid barrel ring, a detent-ball sling plate/dimpled mag cap will not fix the problem.

Solutions seem to be (others, feel free to add to this list):

1. Buy wingmaster/police barrel with detent in barrel ring (and appropriate mag cap)
2. Have detent put in Express barrel (again, with appropriate mag cap)
3. Periodically hand tighten/tape threads
4. Use a magazine extension and clamp

 

[plateshooter]

I got an O ring that fit over the magazine tube. Install the forearm, then the O ring then the cap. The tension of the cap against the rubber O ring will eliminate the problem, at least it does for me on my 11/87 after removing the dimples.

 

[RMc]

Any sling mount of this type can:

Any sling mount of this type can be modified to work with a standard 870 cap - no need for expensive gunsmithing or buying a new barrel.

http://www.wilsoncombat.com/sa_slings_mounts.asp

 

[ChCx2744]

Okay I have questions regarding this issue as well...What is the "Detent?" What is the "Retainer?" What is the "Follower?"

Now I hope I'm not mistaken so please bear with me:

I'm GUESSING the DETENT is the loop-like thing that kind of "hangs" off of the bottom of the barrel that goes over the magazine tube to stabalize the barrel to the tube and frame?

I'm GUESSING the RETAINER is the part that goes on the FRONT END of the magazine tube spring that touches the magazine cap?

I'm GUESSING the FOLLOWER is the part that goes on the REAR END of the magazine tube spring near the port where you actually insert the shotgun ammo?

The reason I ask is because I don't want to mix up and at the same time be able to correct others who get the parts mixed up as well. I am also planning on a "dimplectomy" or whatever cute term people use lol...I wanna add a mag tube extension on my express as well; my warranty is about to expire. I hope this thread doesn't get slept on

 

[Virginian]

This has been a problem with Remington guns since Remington started using magazine caps.

I've got to call BS on this one. I have been shooting Remingtons, way more than one, for going on 50 years, and the only problem I have ever seen is a loose nut on the back of the stock. Unless someone either screwed up the original set up, or started switching around components that weren't designed to work together in the first place, I have yet to see a problem. The originals had the detent retainer arrangement, and the later Expresses used the toothed plastic retainer that needed the magazine tube dimples. Once someone switches caps, drills out dimples, and/or adds a magazine extension and has a problem, I think they have a lot of nerve blaming Remington. When you change something, think about what can happen, and deal with it.

 

[dfariswheel]

I'm GUESSING the DETENT is the loop-like thing that kind of "hangs" off of the bottom of the barrel that goes over the magazine tube to stabilize the barrel to the tube and frame?

I'm GUESSING the RETAINER is the part that goes on the FRONT END of the magazine tube spring that touches the magazine cap?

I'm GUESSING the FOLLOWER is the part that goes on the REAR END of the magazine tube spring near the port where you actually insert the shotgun ammo?


The loop or ring on the barrel is the barrel support ring.
The Detent is the tiny spring-loaded ball on the front face of Wingmaster and Police barrel support rings.
The Express models do not have the detent, they use a different system of retaining the magazine cap.

The retainer is the magazine spring retainer that goes on the front end of the magazine spring.
The Wingmaster and Police models use a split steel "spring-cup" device that is held inside the end of the magazine by friction.
The Express models us a longer plastic tube that fits into the magazine tube and is retained by interlocking with two "dimples" or lugs that are pressed out of the inside of the tube.
Coarse "teeth" on the end of the plastic retainer interlock with the inside of the Express magazine cap to hold the cap in place.

The follower is the part that goes on the rear end of the magazine spring and pushes the shells down the tube.

Once the dimples are removed, there's no way to keep the magazine cap from vibrating loose.
One of the best ideas I've heard for this is to just go to the hardware store and buy a large rubber "O" ring that will just fit over the magazine tube.
Put the barrel on, put the "O" ring over the tube and screw the cap on snug.

 

[augustino]

loose barrel cap remedy...

I'm personally not familiar with this problem. I have several 1300 Winchester's and never had this happen. BUT with other applications, when a screw, nut, bolt or whatever had a tendency to come loose with regular use I applied a drop or two of the REMOVEABLE Lock Tight thread sealer. It's a thick liquid you apply SPARINGLY to the threads and after a minute or two, well as the name says it's locked tight!
It comes in several color coded strengths. The red I THINK is pretty permenant. Yes you can remove it with tools but it takes some muscle. So it will not come loose with use. Then ther's the blue stuff. It's made to hold tight BUT come free easily when a wrench or screwdriver is used. Auto parts or home supply centers carry the full line of thread lock-sealers. With this stuff it's clean and neat and no tape to fool with.
Anyone have any experience with it, please sound off.
Thanks and good luck with the 870 it's a great SG!!!

 

[xm21]

Brownells sells wave washers for 1100's that keep the cap tight when you replace the foregrip with one that has no detent ball.