Page 1 of 4 123 ... LastLast
Results 1 to 10 of 35

Thread: School me on 9mm ARs.

  1. #1
    Join Date
    Feb 2008
    Posts
    2,873
    Feedback Score
    30 (97%)

    School me on 9mm ARs.

    With the introduction of USPSA PCC, I'm in the market to build a 9mm AR.

    Do they use regular 5.56 AR free float rails?

    I see there's a 9mm buffer, I'd it necessary over a carbine or H1?

    Which is better, Colt SMG or Glock lowers? As far as reliability in feeding goes.

    Can I use a standard stripped upper I have laying around?
    I must study politics and war, that our sons may have liberty to study mathematics and philosophy. - John Adams

    Urge your reps to sign the hearing protection act.

    http://www.fightthenoise.org/?mc_cid...eid=f994c12c6e

  2. #2
    Join Date
    May 2006
    Location
    VA/OH
    Posts
    29,087
    Feedback Score
    33 (100%)
    Quote Originally Posted by Caeser25 View Post
    With the introduction of USPSA PCC, I'm in the market to build a 9mm AR.

    Do they use regular 5.56 AR free float rails?

    I see there's a 9mm buffer, I'd it necessary over a carbine or H1?

    Which is better, Colt SMG or Glock lowers? As far as reliability in feeding goes.

    Can I use a standard stripped upper I have laying around?
    Colt 6951 is the standard. With that said, lots of companies are making lowers that accept Glock mags. You will want to use an upper geared toward a 9mm. Some rails will work, but others will need a spacer between the upper receiver and barrel.

    You will want to us a 9mm buffer and spacer.



    C4

  3. #3
    Join Date
    Feb 2008
    Posts
    2,873
    Feedback Score
    30 (97%)
    Thanks. Will a BCM rail work?
    I must study politics and war, that our sons may have liberty to study mathematics and philosophy. - John Adams

    Urge your reps to sign the hearing protection act.

    http://www.fightthenoise.org/?mc_cid...eid=f994c12c6e

  4. #4
    Join Date
    Jul 2014
    Posts
    113
    Feedback Score
    0
    To save you some trouble googling, the PSA 9mm glock lowers do not have last round hold open. They do supposedly have a separate lower with that feature, but I've never seen or used one. They also have a colt pattern lower as well. Their uppers are interchangeable afaik. Sorta regret the purchase, but at the same time its a blasting gun. I've only put a few magazines through the gun and haven't had any issues (doesn't really say much). Basically waiting on the stamp to move forward with it.
    Last edited by abso; 11-23-16 at 10:26.

  5. #5
    Join Date
    May 2006
    Location
    VA/OH
    Posts
    29,087
    Feedback Score
    33 (100%)
    Quote Originally Posted by Caeser25 View Post
    Thanks. Will a BCM rail work?
    Yes.


    C4

  6. #6
    Join Date
    Sep 2009
    Location
    Barre, VT
    Posts
    5,989
    Feedback Score
    85 (100%)
    The BCM Keymod worked on mine but I traded with a buddy for Samson rail because i wanted a larger diameter so my can will fit inside the rail.
    "Real men have always needed to know what time it is so they are at the airfield on time, pumping rounds into savages at the right time, etc. Being able to see such in the dark while light weights were comfy in bed without using a light required luminous material." -Originally Posted by ramairthree

  7. #7
    Join Date
    Oct 2016
    Location
    USA
    Posts
    5
    Feedback Score
    0
    As far as rails go, I know DD, Larue, MI FF rails work well, Most should work ok just match the length of rail to barrel length and you should be good to go, You dont need a heavy robust rail though pick out a lightweight such as the MI.
    With buffers, the 9mm buffer is slightly longer then a 556 carbine buffer, they do make a spacer that goes in back of the recoil spring so you can use a 556 carbine buffer, but I'd stay away from that and just get a dedicated 9mm buffer.
    I read about people having problems with the colt style lowers with feeding problems, but I like them, if you load your NEW magazines and let them sit for a week or two the springs settle, and they load easier and reliability is great, I happen to have great success with ASC mags. I bought one metalform brand mag and had problems with the follower, I will not buy any more of those, other people will say the are good. Stay away from the Mag inserts that adopt a regular AR lower to work with colt style mags. The dedicated Glock mag lowers are good to go, there are other options out there, seen one that uses Beretta mags.
    As far as uppers, the gas tube hole is usualy not drilled for the 9mm, ejection port door and additional large deflector are used. Also you dont need the FA it just ads weight. With that said, it be best to just buy a dedicated upper receiver. Your going about it right, ask questions and shop around and see whats out there be spending your $. Good luck

  8. #8
    Join Date
    Dec 2011
    Location
    O'ahu
    Posts
    4,155
    Feedback Score
    61 (100%)
    Why an AR vs one of the SMG options?


    Sent from my iPhone using Tapatalk
    Sic semper tyrannis.

  9. #9
    Join Date
    Dec 2006
    Posts
    144
    Feedback Score
    0
    9mm ball is cheaper then .223 ball and when setup right the 9mm AR will have closer recoil to a .223 AR is one reason. Another is that you can tinker with a 9mm AR a lot more and cheaper then a Sig MPX, CZ Scorpion or MP-5 clone. I picked two 9mm AR lowers: one for a practice gun and the other mostly just for the gee whiz factor of a SBR 9mm AR although I'm thinking the gee whiz factor of two 9mm AR SBR's may be better now.

  10. #10
    Join Date
    Jan 2012
    Posts
    463
    Feedback Score
    14 (100%)
    I have a PSA Glock lower with lrbho. I also had a qc10 with the same setup. Neither lowers work reliably for lrbho. But other than that they work great. I also have a Hahn mag block adaptor for colt mags and it also works great.

    On my last 9mm upper build I went with a utg pro rail. I was just trying to make a cheap blaster upper. I have to say, for the money, it is actually not a bad rail.

    So far I have only ever used the 9mm buffer from heavy buffers. It is a heafty peice, but I have no complaints with it.

    Sent from my Z797C using Tapatalk

Page 1 of 4 123 ... 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
  •