AR-10 bolt not locking back with 30P-1 attached

Discussion in 'Silencers' started by rg1911, Mar 31, 2014.

  1. rg1911 New Member


    While testing loads for my AR-10 (.260 Remington) with my 30P-1 attached, of 35 rounds, the bolt locked back only 4 times.

    The magazine is a new Armalite 10-round magazine. I was single-loading the cartridges.

    The rifle functions correctly without the 30P-1 attached.

    Any suggestions as to how to correct this problem will be appreciated.

    Thank you,
  2. Zak Smith Operations

    • Instructor
    Zak Smith
    Normally failing to lock back is due to not enough gas pressure or weak magazine springs.

    AR-15 or AR-10 that is in the middle of its performance envelope should not have adverse effects from mounting a suppressor. If it's already biased towards a not working state but not quite there, the change in gas pressure/profile can for sure push it over the edge.

    However, if the bolt carrier group cycles so fast that the follower does not have time to rise, it cannot lock the bolt back.

    If you can rule out magazine or spring problems you could try an adjustable gas block
  3. rg1911 New Member


    Thank you. I'll see if I can find an adjustable gas block that will fit the very heavy barrel on the AR-10. The AR-15 may have to wait for its new barrel to arrive.

    I didn't even consider that I'd need to reduce the amount of gas being vented back to the bolt. However, that might explain the damaged .260 case heads.

    Note: I also posted to the Sniper's Hide forum before I saw this response from you.


Share This Page