Featured AR-15 problem

Discussion in 'General Firearms Discussion' started by Galloway6, Sep 29, 2017.

  1. Galloway6

    Galloway6 Possum Lodge Member Supporting Member

    I finally got to the range today with th ar I put together and first pull bang, second pull just a click. I had to pull the charging handle to chamber a round everytime.
    What did I do wrong?
     
  2. lklawson

    lklawson Staff Member

    I'm guessing a gas tube issue. It's not bleeding enough gas to operate the bolt. Might be a blockage, disconnect, or some other related issu.

    Just a guess.

    Peace favor your sword,
    Kirk
     
    SDProf likes this.

  3. ajole

    ajole Supporting Member

    I assume it's ejecting ok?
    How far is the brass going?
    Did you build the upper?
    Barrel length?
    Gas block particulars?
    What gas system?
    What buffer? What buffer spring?
    Bolt...gas key tight?
     
  4. Dane

    Dane Supporting Member

    As mentioned how much did you do on this build?
     
  5. Galloway6

    Galloway6 Possum Lodge Member Supporting Member

    I put the upper together.
    Ejecting OK from what I recall.
    16" barrel
    Mid length gas system
    Bolt and gas key are tight.
     
  6. Could be not enough oil on BCG/oil in gas ring hole. Run it wet, almost to the dripping point.

    BCG moving too fast and not extracting next round correctly.

    Too light of Buffer. Go heavier to slow down BCG.

    Who's barrel being used? The gas hole might not be drilled out enough. Need measurement of hole or it might say from barrel manufacturer site.

    Who's magazines ya using? Might be a bad mag spring in that mag. Try others.

    Del
     
    Last edited: Sep 29, 2017
  7. Galloway6

    Galloway6 Possum Lodge Member Supporting Member

    It is an Anderson complete lower.
    Might be not enough oil, how much should there be?
     
  8. Dad_Roman

    Dad_Roman Supporting Member

    Lots. Initially I will wet a BCG and the upper to dripping and wipe it down. Once its run a couple hundred and had a chance to get broke in you can cut back a bit. Light lube in the lower, standard trigger type maintenance.
     
  9. moona11

    moona11 King of you Monkeys Lifetime Supporter

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    Post pics of the lower inside. The BCG must be able to be placed standing on the bolt with the bolt extened. If not replace the 3 rings. Have you done a function check with the upper not engaged. Then a full function check with the upper engaged? Check the bolt. Ejector pin should be stiff but movable with a punch. Take the bolt apart is the spring and rubber donut or tab in place?
     
    OldOutlaw likes this.
  10. greg_r

    greg_r Lifetime Supporter

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    Sounds like a gas problem. Your bolt is going back far enough to eject, but not far enough to strip the next round.

    I start at either end and work to the middle. Remove the gas block. The port in the block is larger than what's in the barrel. Ideal to have the port in the barrel surrounded by equal amounts of soot. You should not have the edge of the soot ring intersecting the port. If that's good go to the buffer. What weight are you using? If it's an H3, try a H2 and so forth until the bolt locks back on an empty magazine. ( I am assuming a gas problem as my best guess ).

    If you are using the lightest buffer, do the tests on the bolt as described by moons. If the bolt is good, go back to the gas port and enlarge it, a small amount at a time until it functions properly. Go easy, you can always take off more, but you can not add back. Hopefully (and likely) you will have found your problem before you get to this point.

    Nothing wrong with working to the center outwards either. Sounds like moonz does it that way. Just not my preference. Usually when I find this problem it's because the gas block is not centered over the port.
     
  11. moona11

    moona11 King of you Monkeys Lifetime Supporter

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    Was the upper assembled when you got it or did you assemble it?
     
  12. greg_r

    greg_r Lifetime Supporter

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    Said he assembled it.

    Supporting Member
    I put the upper together.
    Ejecting OK from what I recall.
    16" barrel
    Mid length gas system
    Bolt and gas key are tight.
     
  13. SavageGuy

    SavageGuy Supporting Member

    Check the gas block and make sure it's centered and seated properly
     
  14. OldOutlaw

    OldOutlaw Supporting Member

    After the first fire, did the next round feed off of the magazine and into the chamber? All the way in allowing the bolt to lock?
     
  15. Rachgier

    Rachgier Administrator Staff Member

    Quick way to test if the bolt is going back far enough is to fire a single round on an empty mag. If the bolt locks back, it's usually not a gas issue.
     
    Galloway6, moona11, ajole and 2 others like this.
  16. Galloway6

    Galloway6 Possum Lodge Member Supporting Member

  17. Galloway6

    Galloway6 Possum Lodge Member Supporting Member

    BCG stands on end
    Doesn't feed the next round, I have to pull the charging handle to feed the next round.
     
    Last edited: Sep 30, 2017
  18. greg_r

    greg_r Lifetime Supporter

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    I still think it's undergassed. Bolt going back enough to eject but not to strip the next round. If you put one round in the mag, fire the one round, does the bolt lock open on the empty magazine?
     
    Dane likes this.
  19. Rachgier

    Rachgier Administrator Staff Member

    Sounds like familiar advice. Makes me wonder if people actually read previous posts before giving their opinion.
     
    2012gt and moona11 like this.
  20. Galloway6

    Galloway6 Possum Lodge Member Supporting Member

    I will try 1round to see if the bolt locks open when I go back to the range.