Building an AR Style Handgun Chambered in 9mm with The Punch of a Carbine
ATF Reverses its Decision, so You Can Now Shoulder an AR-15 Pistol
9mm AR-15 Pistol Build
by Mike Garman
If you read our articles on AR-15 Basics, you know that they come in all sizes, shapes and calibers. One of the more popular AR types being sold today is in a pistol caliber. The one I decided to build is in 9mm.
Starting with a stripped lower from Palmetto State Armory, the PA-X9 9mm Billet Hybrid Glock lower looks like any other AR-15 lower receiver assembly until you look at the mag well, which is designed to use a 9mm Glock 17 magazine. A standard AR-15 lower parts kit will work with this lower and I elected to go with a CMC Drop-in Standard Trigger Pull Flat with anti-walk pins to keep it in place. The lower is designed to work with a special Glock Cut Bolt Carrier, which allows the use of Glock magazines. The buffer tube, buffer and spring can be standard 5.56 or specialized 9mm parts, which is what I used. These 9mm parts are designed to make the action cycle more reliable than the standard parts.
The upper chambered in 9mm also came from Palmetto State Armory, and was completely assembled by them. I used a 10.5” barrel with a full rail system for mounting lights, lasers or whatever else you’d like. For this configuration I put a Bushnell red dot sight on, which works quit well.
Using the 10.5 inch barrel the AR can either be made into a short barreled rifle or a pistol. Since I didn’t want to deal with the ATF, I went with a Shockwave Blade pistol stabilizer, instead of a stock, that comes with an ATF clarification letter. This letter states that when used as intended** the stabilizing brace is a brace and not a stock. Up until March 2017, if you used a brace and shouldered the gun as Tatiana is demonstrating below, you were technically in violation of the law because you had redesigned the brace. However the ATF has amended their opinion thanks to SB Tactical, who sought clarification of the agency’s 2015 ruling. However, I highly recommend you carry a copy of both the ATF 2015 and 2017 letters when you go to the range to shoot.
** In a letter from Marvin G. Richardson, Assistant Director, ATF Enforcement Programs and Services to the Outside Counsel to SB Tactical, LLC, and dated March 21, 2017, Richardson clarifies that a stabilizing brace placed against the shoulder is legal as long as the brace strap has not been removed from the accessory and/or it has not been permanently affixed to end of a buffer tube. You can download the clarification letter here: SB Tactical ATF Letter. For a layman’s understanding of the ATF’s clarification, you can visit the NRA’s Institute for Legislative Action website.
Being all of the controls are standard AR-15, shooting this 9mm version is very intuitive, and since the weapon is fairly heavy it has virtually no recoil that makes it loads of fun to shoot. Glock magazines are easy to come by, but one thing to keep in mind is that while factory Glock magazines work with no problems the same can’t be said for aftermarket magazines. The Mec-Gar brand ones that work fine in my Glock won’t run in this 9mm AR-15 pistol.
If you live in an area that will let you own an AR-15, I highly recommend that you build or buy one in 9mm. They are loads of fun to shoot and if your primary handgun is also in 9mm, it will greatly reduce the amount of ammunition that you have to carry during a Zombie Apocalypse. By scouring the Internet and doing the work myself this 9mm AR-15 Pistol build cost less than $600.