Lone Wolf’s G9 Carbine looks like any another modern sporting rifle until you check the magazine well. The G9 lower uses small-frame Glock pistol magazines, which solves the problems of previous 9mm AR carbines and makes it an affordable, reliable, and fun gun.

Modern Sporting Rifles (MSR), also known as AR rifles, are commonly used for self defense, hunting, and competition, and are ubiquitous among military and police. Whatever your application, pistol-caliber carbines are accurate, fun, great training platforms, and cheap to shoot. Lone Wolf did their homework and came up with the G9 Carbine.

Most people opt for the 9mm upper, but Lone Wolf also offers uppers chambered in .357 SIG, .40 S&W, .45 GAP, and 5.7x28mm. The uppers are matched with the appropriate GLOCK magazine, except for the 5.7x28mm, which uses top-mounted FN magazines. Buy different uppers, make different guns.

Lone Wolf G9: Pistol-caliber AR, Powered by Glock Mags

The idea of a 9mm carbine is not a new one. Submachine guns have been around for decades, but carbines are a little larger with better ergonomics and are more manageable. In 1981, Marine and genius firearms designer Maxwell Atchisson was thinking about the XM-177.

Lone Wolf G9: Pistol-caliber AR, Powered by Glock Mags
Photo courtesy of guns.connect.fi

The XM-177  was a variant of the M-16 with a 10.5″ barrel. The short barrel wasted a lot of energy as flash and noise, and got very dirty quickly.

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Lone Wolf G9: Pistol-caliber AR, Powered by Glock Mags

Atchisson realized that the XM-177 would be much better if chambered in 9mm. He was a genius and could just do stuff like that. His 9mm gun was a closed-bolt, simple blowback-operated select-fire machine gun.

His blowback system consisted of a heavy bolt resting against the base of the 9mm cartridge case, with a heavy buffer and recoil spring compressed by the kinetic energy of the bolt when it moves back under recoil. The stored energy of the compressed spring then drives the bolt forward back into the firing position. This eliminates the whole gas system, allowing the use of very short barrels. For close quarters, it had all the energy it needed in a small, low-recoil package, with the great ergonomics of the M-16. A 10.5″ barrel is the sweet spot for 9mm, giving nearly optimum energy.

Colt took over the project and in 1985, introduced the 9mm SMG. More interested in parts commonality with the M-16 than innovation, they came up with a rough, mass-produced product still sold by Colt today. The Marine Corps adopted the 10.5″-barrel model for the Fleet Antiterrorism Security Teams (FAST), and it was used by DOE, DEA, U.S. Marshals Service, and the U.S. Diplomatic Security Service. The Bahamas, Bangladesh, Malaysia, and Panama also fielded the SMG.

Lone Wolf G9: Pistol-caliber AR, Powered by Glock Mags

There were several problems with the SMG. A special heavy black buffer was designed to keep the cyclic rate below 1,000 rpm, as a standard 5.56mm buffer would run at 1,250 rpm. Because the direct-blowback design created such high bolt speeds, bolt catches, as well as the trigger and hammer pins, were prone to breakage. The pins were upgraded to nickel-plated stainless steel.

Colt decided to use modified Israeli UZI magazines. Their version has narrow feed lips, making them very hard to load, prone to double feeds, and they wear quickly. C Products makes a very good SMG magazine for this model.

Inspired by the SMG, Lone Wolf has reinvented the AR in pistol calibers and addressed the magazine issue by adopting the solid and widely available Glock mags.

Field testing

I gathered my equipment for the test. I had an assortment of 9mm and .40 ammo. The 9mm was mostly Georgia Arms 9mm Luger 115-grain plated total metal jacket. It is great ammo at a fair price.

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I used LULA loaders to load up my mags. Some people ridicule the use of magazine loaders, but when you are loading 1000 rounds at a time, it makes a difference. I had plenty of Glock factory mags of various sizes and some 33-rounders of uncertain Asian origin.

Lone Wolf G9: Pistol-caliber AR, Powered by Glock Mags

Lone Wolf sells their guns as separate lowers and uppers to allow the shooter the greatest flexibility. There are pistol and carbine lowers, and pistol- and carbine-length uppers. If you live in a free state, $200 and an ATF form one will allow you to build your very own short-barreled rifle. The G9 design makes for a very reliable pistol if you prefer that option. Near maximum velocity is reached at about 10.5 inches of barrel, as previously stated. To avoid imperial entanglements, I used the Lone Wolf carbine lower and 16″-barreled uppers in 9mm and .40 caliber.

Lone Wolf G9: Pistol-caliber AR, Powered by Glock Mags

Making a reliable bolt hold-open for AR pistol carbines has proven impossible with current technology. Other manufacturer’s bolt hold-opens suffer from reliability problems. Lone Wolf eliminated those problems by eliminating the bolt hold-open entirely. You shoot it like an MP5 or an AK.

Lone Wolf G9: Pistol-caliber AR, Powered by Glock Mags

I ran over 2000 rounds of every stray 9mm round I could find through the first upper. All of them, even +P loads, cycled fine, but you could sure feel the difference in recoil. The .40 upper went through an equal number of .40 ball and JHP. Glock mags and the G9 carbine worked very well together.  Aftermarket mags were unpredictable and were soon discarded.

Lone Wolf’s G9 uppers all have:

  • Quad rail free-floating rail system
  • A2-style flash suppressor
  • Properly modified bolt for use with Glock magazines
  • 16″ barrel
  • 4150CM ordinance steel
  • Button rifled 1:10 twist rate
  • M4 profile exterior
  • Non-reflective black oxide finish
  • Bolt is mil-spec 8620 material heat-treated to 50>55 RC
  • Bolt is black oxide exterior coated

There are several previous designs floating around out there. Lone Wolf guns are compatible with Colt-pattern uppers, which have an additional groove cut in them to accommodate the ejector. Lone Wolf will modify your bolt for $44.95. Olympic Arms upper receivers are not compatible. Rock River uppers will fit with modification, but their lowers use a dedicated 9mm hammer, which will not work with the Lone Wolf bolt.

The G9 trigger pull weighs in at four and half pounds, which is perfect for practical work. The G9 lower accepts any other AR triggers.

The hardware and the quad rail on the G9 are perfectly adequate, but the G9 is compatible with AR-15 parts. If you like a certain pistol grip, trigger, butt stock, or rail, the G9 will accommodate them. If you have a favorite AR-15, you can customize your G9 for the same feel.

Why buy?

If you already have an AR-15, why buy a G9?  For me, the answer is training. I spend a lot of time on a range that is limited to handgun and shotgun. There are plenty of steel targets. Now, I can run the G9 Carbine using less expensive 9mm or .40 (whichever I have more of) and shoot steel targets that won’t take rifle hits. I am doing drills I never considered before, and there are not many things more fun than shooting steel!

Plus, it uses standard Glock magazines; most shooters already have a few. They are cheap and available everywhere. The new Magpul mags work great in the G9.

A red dot sight makes the G9 even more fun. I used an Aimpoint red dot sight on my G9, and the gun proved to be accurate enough to shoot ragged single holes at 15 yards with no effort at all using a variety of ammunition.

You need a G9. Chances are you already have the magazines, and there are plenty more where those came from. The ammo is available, easy to reload, and affordable. It is fun to shoot and a great training platform. You can shoot it on pistol ranges and shoot steel up close. It is so accurate that you will amaze yourself. Order up your Lone Wolf G9 Carbine today.

(Featured Image Courtesy of Lone Wolf)