MDT LSS Chassis Magazine Feed Issues

Discussion in '223 / 5.56 MVP and Variants' started by Ri22o, Oct 13, 2015.

  1. Ri22o New Member

    Member Since:
    Jul 19, 2015
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    Finally took my MVP out to the range since having put it in the MDT chassis. I thought I had cycled some rounds through it at the house after the install, but I guess I didn't.

    It will not pull a round from the magazine unless I put upward pressure at the front of the magazine (tilting the front up towards the chamber). It appears there is too much slop in the magazine well that the magazine is not where it needs to be in order for the bolt to strip a round from it.

    Has anyone else had this issue with the MDT LSS chassis? Is this a known issue? I tried multiple C-Products 20/30 round magazines, as well as my Mossberg 10 round magazine, and they all needed to be assisted. I did also try one of my Pmags, and while it did work, it was so tight in the magazine well that I wouldn't ever consider using it.

    Thoughts?
  2. cwlongshot Member

    Member Since:
    Sep 9, 2015
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    Well thats troublesome... Sorry no answers, sorry for the troubles...

    CW
  3. Ri22o New Member

    Member Since:
    Jul 19, 2015
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    After some more messing around with it, the issue is still there with the metal GI style magazines, but it appears I have only one Pmag that is tight in the mag well. Of course, this was the only Pmag I had with me at the range, but my other Pmags seem to fit fine.

    I don't want to be required to run only Pmags with this rifle, it defeats the purpose of why I went with a rifle that uses AR magazines. Hopefully someone will be able to shed some light on how to fix this and/or if it is a defective chassis.
  4. spamassassin Well-Known Member

    Member Since:
    Aug 8, 2014
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    It's a not uncommon problem and is not limited at all to the LSS chassis. Some people have taken to pretty cleverly modifying their stocks so there's a little bump at the bottom of the rear of the mag well to cause the front to tip up a tad. My LSS and my factory varmint stock have the issue. Some mags have been much better for me than others. My 20rd was very reliable before a fairly recent meeting with a rock. 10's and 30's seem to be less reliable.

    The problem is characterized by the bolt being happy enough to try to strip a round but the nose of the bullet doesn't make it to any sort of ramp before being stopped cold. When you tip the front of the mag up the rounds clear.

    Perhaps MDT will incorporate a 1 or 2 degree change to the lay of the mag well on a future version. I only use metal milsurp mags so I can't help about the pmags.
  5. Ri22o New Member

    Member Since:
    Jul 19, 2015
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    I never had an issue with my original stock, and thought that with the cost of this chassis that it would work without issues. I shouldn't have to modify the magazine well in order for the most commonly available magazines to work as they should.
    NFA likes this.
  6. spamassassin Well-Known Member

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    there's a wide variation in the tolerances among the various STANAG mags you can get. Find mags your rifle likes.
  7. BSJ Member

    Member Since:
    Jul 6, 2013
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    Yes, it's a known problem. Mine was the same way...

    Contact them and get a replacement.

    My new stock works quite well. I only get a failure to feed with the last round in a couple of magazines...
  8. Ri22o New Member

    Member Since:
    Jul 19, 2015
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    Thanks. I will send an email their way.
  9. BSJ Member

    Member Since:
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    Did you ever get it straightened out?
  10. Ri22o New Member

    Member Since:
    Jul 19, 2015
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    I believe so.

    It started off with my electing to go the less expensive route and they sent me a new magazine release/catch bar. Testing by cycling the action, this did not help.

    They then sent me a new chassis. I have yet to get out and shoot with it since replacing it, but cycling comparing to the old chassis it seems to be a complete change.

    So, for now I would say the new chassis fixed the issue. I am hoping to get out sometime soon and try it at the range to verify though.


    I will add that they were very easy to work with in getting this resolved.
    NFA likes this.
  11. BSJ Member

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    Excellent! There were production issues that left me waiting for a few months, but in the end I got a good chassis.
  12. DINKY DAU Member

    Member Since:
    Oct 2, 2015
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    Just got back from the range for the first time with my new and improved mvp patrol, with LSS chassis and same exact issue, only my p-mag worked. I just talked to tech support and they seemed baffled(BS) told me to submit a request. They said they had issues about 8 months ago but they were all recalled...yeah and put back in stock evidently.
  13. spamassassin Well-Known Member

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    Never recalled mine. It's had minor feed issues with various mags and especially pointy berger bullets from the get go.
  14. BSJ Member

    Member Since:
    Jul 6, 2013
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    Recalled? No way. If I hadn't read about it here, I'd still be stuck with a bum stock!
  15. DINKY DAU Member

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    Oct 2, 2015
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    Got a reply, they never had this issue! BULLS$&@!!!
  16. bombadillo Moderator

    Member Since:
    Mar 19, 2012
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    I had the same issue, and the only thing that alleviated it was to run the Magpul mags as well.
  17. cwmoss New Member

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    Oct 30, 2016
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    I had one of these chassis on a Tikka doing the same thing. I called MDT and after speaking with a fellow, he sent me some different latches. They were different lengths. I used the shortest, which held the mag tighter to the action, which cured the problem. The one that came with the chassis, I think, was the longest of them all.
    DINKY DAU likes this.
  18. DINKY DAU Member

    Member Since:
    Oct 2, 2015
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    Hey, after your post I emailed MDT to try and get the latches and they are sending a replacement chassis...I didn't argue.


    Sent from my iPhone using Tapatalk
  19. cwmoss New Member

    Member Since:
    Oct 30, 2016
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    Be aware that if they send you a new chassis with the same length latch that you now have, your problem will still be with you. The latch needs to hold the mag tighter to your action.
    DINKY DAU likes this.
  20. spamassassin Well-Known Member

    Member Since:
    Aug 8, 2014
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    Just tested with pmags, flawless feeding.

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