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870 mag cap??

Discussion in 'Tactical Shotguns' started by team9x19, Oct 12, 2011.

  1. team9x19

    team9x19 the bee's knees

    May 29, 2010
    central MO
    So I took my 870 out yesterday amongst other goodies for a long range day extravaganza. I got about 80 rounds through my 870 until a round was fired (last in the gun). There was a bang, and then the sound of metal hitting gravel. A split second later and I noticed that the factory extended mag tube, spring, and magazine cap/ union nut was on the ground. Upon further inspection it appeared that some threads on the mag cap -- not from the portion of the extended of the mag tube, but from where the extended mag tube attaches to the "standard length" mag tube are sheared off. I should mention that I have a GG&G front sling attachment mounts in between the mag cap and the "standard length" tube. I am thinking this problem can be attributed to the fact that the GG&G front sling mount does not allow all of the threads of the mag cap to be utilized, due to the extra space of the sling attachment itself.
    I have been looking around for some aftermarket type mag caps that are not so -- I suppose, inferior.
    Any suggestions?

  2. SCSU74

    SCSU74 St. Cloud Proud

    Jul 24, 2010
    The Northwoods
  3. team9x19

    team9x19 the bee's knees

    May 29, 2010
    central MO
    is there any company that makes a durable mag cap? I have no issues with my factory remington extended mag tube -- it is the six shot tube, and i need a mag cap that screws onto the factor standard length mag tube, and also has threads out the top of the cap itself for the extended portion of the tube to screw into as well.
  4. Glock411


    Mar 22, 2007
    Never had a problem on any of my 870's all have the factory remington extended mag tube, I Did have a few feed problems on my first 870, Purchased a Wilson spring and follower problem solved, After that I automaticaly did the same on my other two 870's, Never had a problem at all, All three of my 870's have pumped easy 100's of rounds.

    Is it possible it just was not tight and became loose ?
    Last edited: Oct 12, 2011
  5. aippi


    Jun 12, 2009
    The added on sling plate is causing the issue just as you said. You mag tube is susposed to be 11.5" long. Even if it is exactly that there is little room for after market plates that eat up some of the space needed for the magtube coupling to completely thread on. I see a lot of mag tubes at 11 3/8 and that is asking for a problem when you add an after market plate.

    Loose the plate and the poblem is over unless of course you have damaged the threads on the Magazine tube and that is a factory repair. They may also void any warranty as the issue was caused by an after market problem. Take the plate off and see if the mag tube coupling will thread on to the mag tube. If so, there will be no issue.
  6. team9x19

    team9x19 the bee's knees

    May 29, 2010
    central MO
    the mag cap does have threads that are sheared off.. I'm going to ditch the factory remington 2 round extension and go with a Wilson Combat one. I am also going to add the Mesa tactical barrel clamp to attach a light/ quick release sling post.

    EDIT: I am also quite peeved at GG&G since I left them a message about this and asking for a call back, which was a week ago and still haven't heard anything .. I'm going to try and call again just to explain the issue and how I believe it is directly (obvious) related to their sling adapter being the root of the issue.
    Last edited: Oct 16, 2011