[SHOT 2016] Quarter Circle 10’s Glock Mag AR Pistol

Quarter Circle 10 had a very strong line up this year at their booth consisting of several flavors of AR pistols chambered in pistol calibers. Danny walked me through the lineup of their pistols that accept Glock magazines and feature a last round hold open. Currently available in 9mm, .40 S&W, and .45 ACP you can choose either the large frame Glock lower or the small frame Glock lower depending on the caliber you want. Quarter Circle 10 also offers a Colt SMG mag version as well. Barrel lengths on the pistols are available in 3.5″, 5.5″, 7.5″, 10.5″, 14.5″, and 16″ depending on the end users requirements.

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Quarter Circle 10 will be offering these as factory machine guns to law enforcement and military, sorry everyone else ATF says we aren’t cool enough. The stand out feature on the Glock mag lowers is the fact that it has a last round hold open, something many other manufactures gave up on and decided to abandon. Quarter Circle 10 says there are no plans at this time to offer a factory SBR, but that may change in the future. The pistols on display were sporting a stabilizing fin to make it compliant. The MSRP will be right around $1000 and head up from there depending on configuration.

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  • BattleshipGrey

    I’m guessing Glock missed its window for a carbine. I’m glad to see more companies taking on Glock mags though for PCCs.

    • Machinegunnertim

      They will come out with one in 6 years, ensure that it has a terrible grip and trigger as well as more recoil than it’s competitors and $100 to $500 higher price. And many will claim that’s it’s a ground breaking innovation! And the most exciting thing Glock has done yet!
      That’s just my prediction, and you are spot on. Glock misses the boat all the time yet their aggressive marketing keeps them more than afloat.

      • BattleshipGrey

        I think their reliability, simplicity and low cost decent mags has something to do with keeping them afloat as well. If you’re including aggressive marketing to LE then yes. One could say they are very aggressive in that regard. Or were you meaning the civilian marketing?

        • Nicks87

          Sig is far more aggressive when it comes to LE marketing. Right now, there are quite a few depts. switching over to Sig just because they are willing to make sweet heart deals.

        • Machinegunnertim

          The reliability and simplicity has been matched by nearly everyone else and at a lower cost too. Also with a far better grip and lower recoil impulse. The robust and cheap mags are a win for Glock , but their thickness limits capacity.

          By marketing I mean how they have made sure that many movies and TV shows and video games have their gun. As well as other merchandise and publicity and celebrities signing on. There are rumors of shady deals to get or keep L.E. contracts but i have no stories to confirm.

      • Nicks87

        Yep because Glocks are so horrible, that’s why most LE agencies issue them. That’s why the Marines made a special request for them and that’s why they continue to out sell most every other handgun.

        • Machinegunnertim

          Over all they are. And any agency that actually does tryouts ends up picking the M&P or something else. The only ones that buy them do it because it’s just what they’ve always done or the neighboring department has them. The Marines got a few (and it’s probably a handful) because they are on the list of NATO certified handguns.
          A large acceptance does not automatically mean it’s the best.

  • Rey

    I approve the Glock AR-45.

  • Rog Uinta

    I built an SBR based on their 9mm lower and it runs great. The last-round bolt hold-open (LRBHO?) works…sometimes. QC10 provides some “tweaking” instructions to get it to work perfectly but I haven’t fiddled with it yet. Given my past experience with 9mm ARs I’m tempted to just leave well enough alone. The fact that it gets through a whole mag without failures is good enough for me.

    It makes for a great suppressor host and runs no matter how dirty it gets.

    • Xanderbach

      I’m tempted by one. I have a colt 633doe clone pistol using colt mags, with a cmmg bolt carrier. Not what I would call reliable, which is sad, since otherwise it would be a great home defense gun.

    • Adam Withem

      I’ve got a suppressed SBR from these guys. TON of fun to shoot. It has been sitting ever since it started sharing a safe with the new MP5 lol.

  • Christian Hedegaard-Schou

    I need one of their large-frame lowers and a DI 10mm upper.

  • miamic70

    It’s made by “Quarter Circle 10” wtf not release it in 10mm? Marketing fail!

    • UVB76

      Thumbs up on a 10mm version.

  • hydepark

    Why go through all the trouble to make this thing and then leave the buffer tube?? I’m not an engineer but for the love of pete why one earth would you keep the buffer tube / receiver extension? Severely limits stock options and no matter what you do it can only be so short now.

    • Patrick R.

      Because the bolt has to go somewhere.

  • Ogee

    They have a great product, but way behind in production and zero customer service. The stated 1-4 weeks wait is 10 and growing with no end point in site. I gave up one the build as I do not want to deal with a company with horrible customer assistance.