Cycling issues

Discussion in 'AR-15 Discussion' started by okieboy, Jul 23, 2014.

  1. okieboy

    okieboy New Member

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    So I took my first AR out today. Built it myself and I can't get the dang thing to cycle more than 1 round. I'll rack a round, bang, usually it ejects but it won't chamber the next round. I had a lot of stoppages. Mostly fail to feed and a few double feeds. I'm guessing I need to adjust the gas pressure but I can't figure up or down.
     
  2. Highpower

    Highpower New Member

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    When you pull the charging handle all the way to the rear, and hold it there - does the bolt head disappear behind the ejection port? Or can you still see a portion of the locking lugs on the bolt showing in the port?
     

  3. JonM

    JonM Moderator

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    good pics of the rifle especially the upper reciever from the underside. pics of the buffer buffer spring and bolt carrier. really good closeups of the carrier itself and the gas block
     
  4. okieboy

    okieboy New Member

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    ImageUploadedByFirearms Talk1406169306.940492.jpg
    This is bolt caught open on bolt catch. When I pull charging handle all the way back it disappears.
     
  5. JonM

    JonM Moderator

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    those look ok.

    can you take the handguards off get a real good close up of the gas tube as it enters the upper and a good close up of the gas block??

    the bcg looks staked would like a real good close up of the gas key on the carrier

    with the bolt extended will it stand on the bolt without the bolt retracting into the carrier??

    how many gas rings are on the bolt?? there should be three

    causes of not cycling is always an issue with improperly assembled gas system parts or incorrect parts put together or a mis-drilled barrel
     
    Last edited: Jul 23, 2014
  6. okieboy

    okieboy New Member

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    The bolt will stand without collapsing. The BCG looks good. I'm trying to take the hand guards off
     
  7. JonM

    JonM Moderator

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  8. okieboy

    okieboy New Member

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    How can I tell if there's leakage?
     
  9. JonM

    JonM Moderator

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    from the side at the base of the key where it attaches to the carrier. if its leaking there will be a LOT of carbon build up it looks greyish to black depending on powder used.

    first part shows how to do a gas ring test

    [ame]https://www.youtube.com/watch?v=jRYXsyS2B98[/ame]
     
  10. okieboy

    okieboy New Member

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    My BCG passes the test plus it's brand new. Today was the first day I've fired it
     
  11. JonM

    JonM Moderator

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    most likely your losing gas at the gas block from either an incorrectly installed gas block or incorrect sized block or leaking gas at the carrier.

    i would lean towards the gas block being the issue.
     
  12. okieboy

    okieboy New Member

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    So is there anything I can do to fix it?
     
  13. okdonk

    okdonk New Member

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    This.
    [ame]https://www.youtube.com/watch?v=IqId0PMdPYA[/ame]

    Watch Check #7. This video helped me alot.

    I had the same problem about a month ago when i reconfigured my SBR. What i did was:

    Checked and replaced with brand new gas tube and gas block. Make sure they are properly aligned. JonM did write up a thread about how to properly align them.
    I tried using different kind of buffers like Carbine, H and ST-T2. To find out if the rifle using the right buffer, i fired 1 round in a mag, if the BCG locks back to the rear after firing that 1 round means good to go.
    Checked if i have a worn off buffer spring and turned out the spring was worn out. Replaced it with a brand new one.
    [​IMG]
    Checked and polished the feedramp.

    Lastly this video helped me finding out the BCG gas key was leaking. Voila... solved the problem.
     
    Last edited: Jul 24, 2014
  14. okieboy

    okieboy New Member

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    Is loctite really the solution to a gas leak? Can it handle the pressure?
     
  15. okieboy

    okieboy New Member

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    I did the test he showed for gas key leakage and that's definitely the problem. What strength loctite should I use? I have a small bottle of the (red) I think. The one meant for sights that can be taken apart by stuff hand pressure.
     
  16. okdonk

    okdonk New Member

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    The loctite 620 retaining compound will fix the issue. But it's better to get a brand new gas key and fasteners.
    http://www.bravocompanyusa.com/BCM-Gas-Key-p/bcm gas key.htm
    And you need to stake them too.

    Mine was BCM BCG, i was suprised it leaked. I shot it like approx 500 rounds maybe and purchased it slightly more than a year ago.
    Emailed BCM the issue, couple days later, they emailed me a shipping label. About a week, the BCM made it's way back to me. They inspected, repaired and test fired it.
    So if you can email the BCG manufacturer, it'd be better. Save yourself the trouble :).
     
  17. okdonk

    okdonk New Member

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    The one you meant was the threadlocker.. that specific loctite will not going to fix the problem.

    This one will, $4.80 shipped.
    http://www.ebay.com/itm/LOCTITE-620...5ml-Hi-Temp-Fills-Gap-Size-015-/151354992380?