Page 2 of 3 FirstFirst 123 LastLast
Results 11 to 20 of 25

Thread: Bolt lock back issue

  1. #11
    Join Date
    Apr 2012
    Location
    43°N 83°W
    Posts
    2,517
    Feedback Score
    1 (100%)
    Load one round of .556 in your mags first then top off with the weaker ammo so your bolt will stay open on last shot for quick reloads. Put hundreds of rounds through it and let it break in. You probably won't have to buy/swap/trouble shoot extra parts that you domt need right now. That's what I'd try on a new BCM...
    'Evil Minds That Plot Destruction'

  2. #12
    Join Date
    Apr 2012
    Location
    Michigan
    Posts
    81
    Feedback Score
    8 (100%)
    I also put my bcm bcg in my v5 to see if it would lock back in my DD and it would not lock back in my DD either. Maybe it needs a lot more rounds through it but I just don't understand why it will lock back sometimes but majority of the time it won't. I really wish I didn't have to shoot the pmc ammo but it is really all that is around this area right now, it is just frustrating to have this issue.
    Last edited by jdm; 04-16-13 at 04:15.

  3. #13
    Join Date
    Nov 2010
    Location
    Virginia Beach, VA
    Posts
    220
    Feedback Score
    6 (100%)
    Quote Originally Posted by Clint View Post
    Must be related to the BCG.

    Try swapping bolts and narrow it down to bolt or carrier.

    Check the gas key and bolt gas rings
    Try this. It will help to narrow down the issue. Just remember to keep track of what bolt goes with which carrier during your testing. All my rifles use BCM BCG and have run flawlessly on whatever I have fed them, including PMC bronze. There's always a chance for a dud with any manufacture, but others are more prone to it. Try swapping bolts around and let us know what happens.

  4. #14
    Join Date
    Jun 2006
    Location
    GA
    Posts
    3,704
    Feedback Score
    43 (100%)

    Re: Bolt lock back issue

    Quote Originally Posted by jdm View Post
    I also put my bcm bcg in my v5 to see if it would lock back in my DD and it would not lock back in my DD either. Maybe it needs a lot more rounds through it but I just don't understand why it will lock back sometimes but majority of the time it won't. I really wish I didn't have to shoot the pmc ammo but it is really all that is around this area right now, it is just frustrating to have this issue.
    It could be that the gas rings are a little tight and need a few more rounds to break in. Try swapping the bolts out and see how the DD bolt runs in the BCM carrier.

  5. #15
    Join Date
    Jan 2008
    Location
    AZ-Waging jihad against crappy AR's.
    Posts
    24,902
    Feedback Score
    104 (100%)
    No where do I see lube mentioned. Lube the BCG generously and shoot it. I would probably look for some M193/855.

    Also check the gas rings and make sure none of them got crossed. I would also use a semi stiff wire and run it into the carrier key go make sure there is no obstruction. If that doesn't help contact BCM.



    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

  6. #16
    Join Date
    Apr 2012
    Location
    Michigan
    Posts
    81
    Feedback Score
    8 (100%)
    Thanks everyone for your advise. Also I have both of my BCG lubed up very good with TW25B. I also sent a email to BCM and I am waiting to hear from them. Does anyone know how to actually get in touch with them to be able to speak to someone on the phone if possible?

  7. #17
    Join Date
    Jan 2008
    Location
    AZ-Waging jihad against crappy AR's.
    Posts
    24,902
    Feedback Score
    104 (100%)
    I would use real lube and not TW-25B. You more than likely will not get them on the phone and they more than likely will encourage you to do some basic troubleshooting yourself.

    Quote Originally Posted by jdm View Post
    Thanks everyone for your advise. Also I have both of my BCG lubed up very good with TW25B. I also sent a email to BCM and I am waiting to hear from them. Does anyone know how to actually get in touch with them to be able to speak to someone on the phone if possible?



    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

  8. #18
    Join Date
    Jan 2011
    Posts
    32
    Feedback Score
    0
    I had an M-4 where the bolt failed to lock back, turned out to be related to the buffer tube that was bent. Because of that the bolt was positioned too far above the bolt catch. I just went to a whole new buffer tube, buffer spring, and buffer, problem solved. That's what I get for buying cheap stuff.
    Better to have it and not need it than need it and not have it.

  9. #19
    Join Date
    Apr 2009
    Location
    FL -Where it's summer 10.5 months out of the year
    Posts
    4,114
    Feedback Score
    17 (100%)
    PMC is notoriously weak...and inconsistently so. Powder charges vary greatly, as evidenced by wide variations in chronograph velocities.

    It is weak even for .223.
    "That thing looks about as enjoyable as a bowl of exploding dicks." - Magic_Salad0892

    "The body cannot go where the mind has not already been."

  10. #20
    Join Date
    Apr 2012
    Location
    Michigan
    Posts
    81
    Feedback Score
    8 (100%)
    BCM told me to change my H buffer to a carbine buffer and see what happens. I changed it out and so far so good. I will change the H buffer back after I get several more rounds through it and hopefully everything will be better. I really do appreciate all the advice.

    I also switched to slip 2000 ewl for lube as well. BCM recommended I do that also.
    Last edited by jdm; 04-30-13 at 02:18.

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
  •