DPMS Sportical Bolt Catch Not Working

Discussion in 'Video How-To's and Tutorials' started by SeismicTrash, Jan 22, 2014.

  1. SeismicTrash

    SeismicTrash New Member

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    Jan 21, 2014
    I attached a slide fire stock on this POS before i fired a single shot. The gun worked like a well oiled machine my 1st time out. I've had nothing but issues with this gun ever since. First, it wouldn't eject hulls after a single shot (defeats the purpose of a semi-auto). Now the bolt catch issue, wondering if I lubed it too much? Using Magpul mags, and decent ammo...
     


  2. A.Texas.Yankee

    A.Texas.Yankee TGT Addict

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    Ah, well now there's a little more to it then. Have you put the original stock back on to see if that resolves it? Have you looked for any wear that's abnormal? Meaning is the bolt rubbing anywhere it shouldn't be? Have you changed anything with the spring or buffer? Is there anything that is preventing the bolt from fully retracting (this sounds likely if your having failure to eject)? Is there anything inside the buffer tube? Over lube isn't likely unless it's caused some type of build up.

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    Last edited: Jan 23, 2014
  3. KiloKilo

    KiloKilo Active Member

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    Wow.......you put a slide fire stock on a .308..??
     
  4. A.Texas.Yankee

    A.Texas.Yankee TGT Addict

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    As long as it's a .308 design (AR 15 might not work too well) it would just be a really fun (and some what painful) way to spend $30 in just a few seconds.

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  5. SIG_Fiend

    SIG_Fiend Administrator TGT Supporter Admin

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    Is it sometimes failing to actually lock open when firing until it's an empty mag and should get a last round hold open? One thing some AR manufacturers have issues with is the gas port being drilled improper sizes, not allowing enough pressure, allowing the gun to short stroke and not consistently get lockback or a full cycle of the bolt (could have other implications with extraction/ejection as well). The only thing though is I've only really seen/heard of this with the AR-15 platform, and typically in .223, so I'm not too sure if any AR-10's from certain manufacturers have had similar QC issues.
     
  6. A.Texas.Yankee

    A.Texas.Yankee TGT Addict

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    I thought that original too but he said he worked flawlessly the first time out. If that was the issue, wouldn't it have failed from day one? Also he would be able to manually lock the bolt back and he states he can't.

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  7. SIG_Fiend

    SIG_Fiend Administrator TGT Supporter Admin

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    The gas pressure thing probably isn't an issue then. Sounds like an out of spec bolt catch or something.
     
  8. A.Texas.Yankee

    A.Texas.Yankee TGT Addict

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    I'm thinking a mod caused this.

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  9. M. Sage

    M. Sage TGT Addict

    Jan 21, 2009
    San Antonio
    If it's been this way out of the box, before you added anything to the rifle, send it back to DPMS.

    Hate to say it, but DPMS has slipped a LOT in QC over the past couple years. They're on my "brands to avoid" list.
     
  10. Dawico

    Dawico TGT Addict

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    Here is what I found while messing with my AR10 the other day (same issue as OP). The bolt catch has a small rounded edge on the face of it. Also the bolt carrier has an aggressive angle cut into the bottom behind the bolt. These two together cause the bolt catch to not hold the bolt open when an empty magazine is released. It works while the empty mag is in place.

    So being the tinkerer that I am, I filed the face of the bolt catch so the rounded edge was gone. Still a no go.

    I think the issue is mainly related to a bad design. With an empty mag in place, the bolt face hits the follower in the mag. This does two things. First it tilts the follower slightly forward and pushes the back up into the bolt catch. Second, the bolt catches on the follower now and the bolt stays open. When you drop the mag the follower pops up and the bolt slams shut. Because of the aggressive angle cut on the bottom of the carrier the bolt catch doesn't have much to hold onto anyways. Even with no mag inserted the bolt catch will not hold the bolt open.

    All that being said, I received my rifle used and many other parts were upgraded. Maybe the catch or bolt itself are not the original parts. Even so, there seem to be many people having the same issue with DPMS AR10s.

    If it is under warranty, by all means have them make it right. From what I am seeing though, unless something is changed in the design, expect it to happen again.
     

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