300blk pistol parts selection

The #1 community for Gun Owners of the Northeast

Member Benefits:

  • No ad networks!
  • Discuss all aspects of firearm ownership
  • Discuss anti-gun legislation
  • Buy, sell, and trade in the classified section
  • Chat with Local gun shops, ranges, trainers & other businesses
  • Discover free outdoor shooting areas
  • View up to date on firearm-related events
  • Share photos & video with other members
  • ...and so much more!
  • I have a registered lower that I plan on pairing with a 10.5" barreled upper after I chop the barrel down from 16" and adding a sba3 brace. The uppers barrel is a carbine length gas, 1:7 twist with a standard ar bcg.

    My question is that of buffer, spring, and gas block selection as I'm a little unsure of what I should look at first. I do want to run super and subs through both suppressed and unsuppressed. I'd rather not have to buy another barrel as it came with the complete upper assambly.
     

    Gcs7th

    Ultimate Member
    Jan 26, 2012
    1,280
    AGC
    Stop!

    Stop! Has this lower been assembled as a rifle before? If you haven’t registered it with the ATF and paid/received your tax stamp you’re on your way to committing a felony.

    If this is a virgin lower or one registered as a pistol you’re all set.
     

    DutchV

    Ultimate Member
    Jul 8, 2012
    4,703
    Adjustable gas block is the simplest way, with standard buffer and spring.
     

    Gcs7th

    Ultimate Member
    Jan 26, 2012
    1,280
    AGC
    I would buy a new barrel unless you are a machinist. AR barrels are cheap enough and if you cut yours down it needs to be threaded and crowned for a muzzle device and to achieve any accuracy. If you plan on shooting supressed you want to be sure the threading is concentric to the bore so you don’t ruin your can.

    I’ve also heard 1-10 is better for stabilizing subsonic loads. But I do not shoot 300blk

    As for gas block there’s a ton of options. I’m very happy with this option for supressed/unsupressed http://www.seekinsprecision.com/select-adjustable-gas-block-876.html
     

    alucard0822

    For great Justice
    Oct 29, 2007
    17,643
    PA
    300 black can easily become undergassed, especially with subs. Unlike 5.56, a pistol-length port works from 8-16" barrels. A 10.5 with carbine gas might not be enough unless the port is drilled. There isn't as much of a need to restrict gas, even with a supressor, so few run adjustable gas blocks. Just buy a barrel and avoid headaches, the brace tube dictates spring length, SBA3 uses a carbine spring, a standard 3oz buffer usually is fine, might try an H1 with supers, but usually too much with subs. One nice thing is 300 tends to be a LOT more forgiving with a big variety of pressure, it will run better with a bit to much than a bit too little.
     

    Users who are viewing this thread

    Latest posts

    Forum statistics

    Threads
    274,921
    Messages
    7,259,056
    Members
    33,349
    Latest member
    christian04

    Latest threads

    Top Bottom