Page 2 of 3 FirstFirst 123 LastLast
Results 11 to 20 of 22

Thread: Possible issue with semi-auto firing more than one round

  1. #11
    Join Date
    Jan 2008
    Location
    AZ-Waging jihad against crappy AR's.
    Posts
    24,902
    Feedback Score
    104 (100%)
    Would you please tell us what lower you have since I missed it.

    Quote Originally Posted by ohnein View Post
    So today I went to an indoor range to test fire and and try different ammo types with my newly built AR-15. I first fired XM193, PMC, Wolf (to test steel case), then Prvi Partisan. My last trigger pull on the magazine loaded with Prvi Partisan 69gr appeared to have fired 2-3 rounds. These were the last rounds in the 20rd PMag I was using.

    This is on semi-auto using a LMT full-auto bolt carrier group with a USGI trigger from G&R Tactical's LPK. (I think it is also LMT.)

    Now, I'm not 100% sure what happened. I had been making slow and smooth trigger pulls. I don't remember double tapping the trigger. I do remember hearing 2-3 shots very quickly and the gun jerked a lot further to the left than it had previously (I was firing left handed). I'm not sure if more than one round even came out. I wasn't counting up to that point. Maybe the extra shots I heard were just other pistols on the range.

    What I want to know is - Is it possible for some malfunction somewhere in the gun to cause 2-3 rounds to fire on a single trigger pull on a semi-auto trigger?


    Note: the safety is also semi-auto.



    Owner/Instructor at Semper Paratus Arms

    Facebook: https://www.facebook.com/SemperParatusArms/

    Semper Paratus Arms AR15 Armorer Course http://www.semperparatusarms.com/cou...-registration/

    M4C Misc. Training and Course Announcements- http://www.m4carbine.net/forumdisplay.php?f=141

    Master Armorer/R&D at SIONICS Weapon Systems- http://sionicsweaponsystems.com

  2. #12
    Join Date
    Feb 2011
    Location
    St. Louis, MO, United States
    Posts
    116
    Feedback Score
    0
    I've had bad disconnector springs from Stag kits that would do this.

  3. #13
    Join Date
    Oct 2010
    Posts
    2,246
    Feedback Score
    5 (100%)
    - Separate the upper and lower.

    - Cock the hammer by pressing it down.

    - Pull the trigger and ride the hammer forward so it doesn't slam against the lower.

    -Keep holding the trigger to the rear and push down on the hammer. The hammer should stay down.

    -Let the trigger forward. The hammer still should not release.

    Do this a bunch of times.

    If the gun fails this test and the LPK is verified to be installed correctly, there is something faulty with either the LPK (probably the disconnector) or with the lower...more likely the problem is with the LPK.

    Start by replacing the LPK (really just the fire control group, or FCG).

    I'm honestly not sure how it's possible to not know if the gun doubled or tripled. Seems like something you would be sure of if it happened.

    If it fails the above test you'll know for sure. But it could pass 99 times and fail once. So for your own peace of mind you should replace the FCG anyway. That's what I would do at least.

  4. #14
    Join Date
    Jun 2009
    Location
    n.e. ohio
    Posts
    25
    Feedback Score
    0
    I experienced a couple double-fires at the range recently, and when I was cleaning the AR afterwards, there was a drag on the firing pin when disassembling and re-assembling it. I pushed a pipecleaner thru the firing pin hole in the bolt carrier and out popped a piece of cleaning cloth..... No more double-fires now.

  5. #15
    Join Date
    Jul 2011
    Posts
    7
    Feedback Score
    0
    Quote Originally Posted by Iraqgunz View Post
    Would you please tell us what lower you have since I missed it.
    The lower is a stripped noveske. It's the non flared version. Marked n4.

    I'll check the FCG when I get back.

  6. #16
    Join Date
    Oct 2008
    Location
    Houston, Texas
    Posts
    4,167
    Feedback Score
    1 (100%)
    sounds like a textbook disconnector issue

  7. #17
    Join Date
    Dec 2011
    Posts
    9
    Feedback Score
    0
    No one mentioned the possibility of soft primers The OP said firing was fine till the last brand of ammo used

  8. #18
    Join Date
    Aug 2010
    Location
    North Florida
    Posts
    2,679
    Feedback Score
    1 (100%)
    Quote Originally Posted by curmudgeon9 View Post
    I experienced a couple double-fires at the range recently, and when I was cleaning the AR afterwards, there was a drag on the firing pin when disassembling and re-assembling it. I pushed a pipecleaner thru the firing pin hole in the bolt carrier and out popped a piece of cleaning cloth..... No more double-fires now.
    That was not the cause of your doubles.

    Quote Originally Posted by straightsilver3 View Post
    No one mentioned the possibility of soft primers The OP said firing was fine till the last brand of ammo used
    That is not the cause of doubles either.

    Quote Originally Posted by Suwannee Tim View Post
    Make sure you are gripping the pistol grip tightly.

  9. #19
    Join Date
    Jan 2012
    Posts
    1
    Feedback Score
    0
    Quote Originally Posted by mini4m3 View Post
    I've had bad disconnector springs from Stag kits that would do this.
    I've had two different Stag/CMT made FCG that did this
    I had posted about it a while ago
    I found that the hammer would fall on release of the trigger
    Stag was always good about replacing for free but gave no idea of why it was happening....I did find some differences in dimensions between the disconnectors but like i said it's happened to me twice

    http://youtu.be/h4F7hi3-i7c this video was from my first problem I had since replaced the trigger with a new one but had the same issue last year during a class with Mike Pannone once again replaced
    Last edited by PiedraFXPD; 01-19-12 at 15:48.

  10. #20
    Join Date
    Jul 2011
    Location
    Montana
    Posts
    370
    Feedback Score
    2 (100%)
    I have had a couple of 2 fers with my Timney Trigger but it is just a bump fire because of the light trigger pull. Wish I could do it on demand, super fast double taps would be great

Page 2 of 3 FirstFirst 123 LastLast

Bookmarks

Posting Permissions

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