Page 1 of 4 123 ... LastLast
Results 1 to 15 of 55
  1. #1
    Join Date
    Nov 2013
    Posts
    299
    Downloads
    0
    Uploads
    0

    Help with new Build Issue PICS ADDED

    I recently built an AR and am having issues. The rounds are not reliably strippingfrom the magazine and chambering. This is most prominent when trying to hamber a round by using the bolt release or manually. Didn't seem to matter how many rounds were in the magazine. Photos below. But first, build details:

    Mega Arms forged lower
    DSG Arms lower parts kit (including reciever extension, carbine buffer and spring)
    BAD BCG (started with a brownells, but swapped it for a BAD when I thought the issue was bcg related)
    Ballistic Advantage barrel
    Magazines used are MOE Pmag, Troy, Lancer, Bushmaster factory and a variety of surplus/DRMO mags from the PD armory.



    Last edited by tappedandtagged; 18 June 2017 at 19:17.

  2. #2
    Join Date
    Jun 2007
    Posts
    5,596
    Downloads
    0
    Uploads
    0
    Have you swapped out the buffer and spring?

  3. #3
    Join Date
    Nov 2013
    Posts
    299
    Downloads
    0
    Uploads
    0
    Only with another carbine weight (from my factory-ish Windham). Same issue.

  4. #4
    Join Date
    Sep 2010
    Location
    PNW
    Posts
    15,286
    Downloads
    0
    Uploads
    0
    Carrier moving too fast?

    Sounds like you've swapped out the most common issues, the BCG, Magazine. I'd try a heavier buffer.

  5. #5
    Join Date
    Apr 2012
    Location
    N. KY
    Posts
    3,055
    Downloads
    1
    Uploads
    0
    Are you saying that with an unchambered round, you can pull back on the CH let it go, not "riding it down", and it won't strip and feed a round? Let me ask you a dumb question. Having tried everything UW has recommended, is it possible you've over loaded the mag by a round? I've seen that happen so many times, it's almost common. This is one of those "I wish I could see it' things. Also, are you shooting factory loaded ammo or hand loads? Good luck to you, I'd bet it's a simple issue, you've just got find it. One of those "DOH" things, like I do.

    FT
    NRA Life Member
    Deplorables Life Member
    Bible and Gun Clinger
    Filthy Stinking Wal Mart Shopper


  6. #6
    Join Date
    Nov 2013
    Location
    Seattle, WA
    Posts
    2,070
    Downloads
    0
    Uploads
    0
    In my mind, there are two reasons why a round won't be picked up by the bolt:
    1) short stroke - the bolt doesn't come back far enough to get behind the base of the next round
    2) bolt over base - the round is just barely too low for the bolt to pick it up

    #1 is a malfunction typically traced back to the gas system, including underpowered ammo, and is a very common issue
    #2 is physical geometry of the weapon: magazine feed angle and the position of the magazine in the well as dictated by the magazine, machining of the lower receiver, and the magazine catch assembly. #2 is less common, but you'll be wasting your time chasing down gas system issues if it is the real culprit. It sounds like you've eliminated mags as the issue, so your next trick would be to swap out the magazine catch. I had one build where the combo of mag catch and lower just didn't reliably work. A different mag catch fixed the issue and that same mag catch worked just fine in a different lower. I seem to recall reading of a lower receiver where the machining for the mag catch was out of spec enough that there was no way to fix it short of replacing the lower receiver.

    I hope that's helpful.

  7. #7
    Join Date
    Nov 2013
    Posts
    299
    Downloads
    0
    Uploads
    0
    Quote Originally Posted by UWone77 View Post
    Carrier moving too fast?

    Sounds like you've swapped out the most common issues, the BCG, Magazine. I'd try a heavier buffer.
    Its not upon firing that it won't strip the round. Its when trying to chamber a round with an empty chamber.

  8. #8
    Join Date
    Nov 2013
    Posts
    299
    Downloads
    0
    Uploads
    0
    Quote Originally Posted by FortTom View Post
    Are you saying that with an unchambered round, you can pull back on the CH let it go, not "riding it down", and it won't strip and feed a round? Let me ask you a dumb question. Having tried everything UW has recommended, is it possible you've over loaded the mag by a round? I've seen that happen so many times, it's almost common. This is one of those "I wish I could see it' things. Also, are you shooting factory loaded ammo or hand loads? Good luck to you, I'd bet it's a simple issue, you've just got find it. One of those "DOH" things, like I do.

    FT
    Yes, you're understanding correctly. I'm not riding it down. Does this with factory and reloads.

    Not an overloaded magazine. When testing, I would load each mag to 30, fire, while holding the bolt release to lock the bolt back upon firing. I would then hit the bolt release to chamber a new round, through the whole 30 rounds. Sometimes it would chamber, sometimes (~20%) it wouldn't. The number of rounds did not seem to make a difference.
    Last edited by tappedandtagged; 18 June 2017 at 19:20.

  9. #9
    Join Date
    Sep 2014
    Location
    S. Carolina
    Posts
    679
    Downloads
    0
    Uploads
    0
    What type of magazine? Magpul or USGI metal perhaps? If they're the metal ones the trick is to leave two rounds out. When we could have 30 rounders in N.Y. all we could have were pre ban USGI mags. Could only load 28 rounds, never 30 for them to feed properly

  10. #10
    Join Date
    Nov 2013
    Posts
    299
    Downloads
    0
    Uploads
    0
    Quote Originally Posted by Tyrannosaur View Post
    What type of magazine? Magpul or USGI metal perhaps? If they're the metal ones the trick is to leave two rounds out. When we could have 30 rounders in N.Y. all we could have were pre ban USGI mags. Could only load 28 rounds, never 30 for them to feed properly
    Magpul, USGI, metal Bushmaster, Lancer. Doesn't matter if downloaded to 28, 20 or even 15.

  11. #11
    Join Date
    Aug 2014
    Location
    Mn.
    Posts
    1,893
    Downloads
    0
    Uploads
    0
    For starters your rifle looks way to dry. Lube the piss out of that thing, real important on a new rifle. Then while its unloaded cycle it 50-100 times to get the parts to mate up. It looks like its hanging up on the feed ramps of the barrel extension, do the bullets have deep gouges on them?
    The best way to survive a violent encounter is to be the one inflicting the most violence.

  12. #12
    Join Date
    Apr 2012
    Location
    N. KY
    Posts
    3,055
    Downloads
    1
    Uploads
    0
    Quote Originally Posted by Stone View Post
    For starters your rifle looks way to dry. Lube the piss out of that thing, real important on a new rifle. Then while its unloaded cycle it 50-100 times to get the parts to mate up. It looks like its hanging up on the feed ramps of the barrel extension, do the bullets have deep gouges on them?
    Wow, I've been through this many times over. Always want to find the fiend to problem to be a simple one. Besides UW, Stickman and Stone, I would do what Stone recommend is looking at, gouges on ammo (my quepstion about factory ammo and hand loads). I'm not really a fan of lubing the shit out of it, kind of guy, unless your shooting old school phosphorous BCG's.

    Hope you get it right. Lot's of guy's/gal's here to help you get it straightened out.

    FT
    NRA Life Member
    Deplorables Life Member
    Bible and Gun Clinger
    Filthy Stinking Wal Mart Shopper


  13. #13
    Join Date
    Sep 2010
    Location
    PNW
    Posts
    15,286
    Downloads
    0
    Uploads
    0
    Quote Originally Posted by tappedandtagged View Post
    Its not upon firing that it won't strip the round. Its when trying to chamber a round with an empty chamber.
    Ok, I'm following.

    Quote Originally Posted by Stone View Post
    For starters your rifle looks way to dry. Lube the piss out of that thing, real important on a new rifle. Then while its unloaded cycle it 50-100 times to get the parts to mate up. It looks like its hanging up on the feed ramps of the barrel extension, do the bullets have deep gouges on them?
    I agree. I can't tell you how many malfunctions are remedied with sufficient lube.

  14. #14
    Join Date
    Aug 2014
    Location
    Mn.
    Posts
    1,893
    Downloads
    0
    Uploads
    0
    Not sure where it started but back in the day people were afraid to over lube so they end up under lubing. Maybe its a carry over from the military of days gone past. I run my rifles wet even more so on a new build.
    The best way to survive a violent encounter is to be the one inflicting the most violence.

  15. #15
    Join Date
    Sep 2010
    Location
    PNW
    Posts
    15,286
    Downloads
    0
    Uploads
    0
    Quote Originally Posted by Stone View Post
    Not sure where it started but back in the day people were afraid to over lube so they end up under lubing. Maybe its a carry over from the military of days gone past. I run my rifles wet even more so on a new build.
    Agreed. I usually lube all my parts before putting a rifle together. Then lube it again after I give the gun time to soak up the first lube.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •