Quarter Circle 10 Lowers: AR-15 + Glock Magazines

Glock Lower

Quarter Circle 10 is now producing AR lowers that accept Glock magazines. The lowers can be had as a small- or larger-frame receiver. The smalls are for the 9mm, 40 S&W, 357 SIG and 45 GAP calibers, while the large frames handle 10mm and 45 ACP.

All of the lowers have a last-round bolt hold open, have a Glock feed ramp and are made of 7075-T6 aluminum. The lowers come with Glock magazine releases, and no modifications to the magazines are needed.

MSRP is $274.95 for the small-frame receivers. Large-frame receivers have not gone on sale yet. The company also sells 9mm and 40 S&W bolts and barrels.

Hat tip to Cymond for the information.

Richard Johnson

An advocate of gun proliferation zones, Richard is a long time shooter, former cop and internet entrepreneur. Among the many places he calls home is http://www.gunsholstersandgear.com/.


  • John

    Why couldn’t these have gone to market BEFORE I built my 9mm AR?!?

    Oh well, looks like I HAVE to build another one…

    • big daddy

      Same here, I used a DDLES, these are the same except he uses 7075. He has the rights to the design. I’m thinking if this guy stays in business I’ll build a .40 once he has all the parts available and can support them. DDLES had a lot of issues with poor business practices.

      • Cymond

        QC10 is the company that was backing John Beaudry/DDLES. After the meltdown over at DDLES, QC10 sued and took over.

        You can see the massive thread discussing it here: http://www.ar15.com/forums/t_3_15/600709_DDLES_Update___Spoke_to_Jon.html&page=85

        • big daddy

          Yes, Ummmm I’ll pass on that, I was reading it as it went on. Jon was very helpful to me with putting the gun together. But he dropped the ball on what could have been a very successful enterprise.

    • iksnilol

      So what, that’s another excuse to build another gun. I don’t think you can complain too much there.

  • John

    looks exactly like the ddles i have…rebranding perhaps?

    • hking

      DDles went under or something, QuarterCircle10 is former employees that bought/obtained the rights and plans to make these parts.

  • AndyT

    These are quite nice. I picked mine up from the FFL on Saturday. Glock mags drop free and it’s nice how the bolt hold open is engineered. Just make sure you either buy a bolt with the cuts for the Glock mags or get your bolt cut if you use one. Mine’s going to be SBR’d for fun

  • Scott Tuttle

    nice but expensive. ouch

  • smartacus

    This is a dandy idea. Swap uppers and mags to go from 45GAP to 357SIG.
    Add an SB15 arm brace.
    *i hope i can find a 9x25Dillon barrel to go with my 10mm mags for the large frame.

  • Phil Hsueh

    Out of curiosity, since they use Glock mags what’s the legality of using a standard cap Glock mag on these if you live in 10 round state? Not that I plan on building a pistol caliber AR but let’s say I did, I own a Glock 22 with pre-ban 14 (or is it 15) round mags, would those be legal to use in one of these if I were to build it as a pistol?

    • Stompy

      In CA a center fire ar pistol has to have a bulletbutton and 10 round mags only. You could build a feature less rifle and use pre ban mags with a standard mag release.

  • Stompy

    JP makes an AR that takes 9mm glock mags. Nice to see some in .45 and 10mm.

  • Cymond

    There have been some really nice guns made with the previous version of these receivers.


  • John Double

    I’m surprised that glock don’t make pistol lowers.