U.S. special operators are in the market for a tiny assault rifle. Finding a weapon that meets the proposed requirements could be difficult, but not impossible. In fact, it actually looks like a gun company has already shown one to the Pentagon. On March 9, 2017, U.S. Special Operations Command (SOCOM) posted a request for information regarding a new personal defense weapon (PDW) on FedBizOpps, the federal government’s main contracting website. Any interested company would have to provide information on a kit that uses the standard M4A1 lower receiver as the core of the gun.

The weapon can’t be any longer than 26 inches with the stock extended, only 7.5 inches high and weigh 5.5 pounds or less. With the stock folded or collapsed, SOCOM wants the gun to shrink to no more than 17 inches long and hopefully just a mere 15 inches. This would make the weapons ideal for troops engaged in close-quarters combat or otherwise in confined spaces, as well as vehicle and helicopter crews. More importantly, however, the small firearms will fire the .300 Blackout cartridges, but will also have the ability to quickly switch to standard 5.56mm ammunition.

US Navy US Navy Explosive Ordnance Disposal personnel train with Mk 18 Mod 1 carbines.

The new cartridge seems to be at the heart of the project. The complete package would offer a handier weapon than a full-size rifle or carbine, but with more firepower than similarly sized 9mm submachine guns or pistols. The gun would also be more powerful than more exotic and compact PDWs on the market, such as the 4.7mm Heckler and Koch MP7 and 5.7mm FN P90. SEAL Team Six reportedly has a number of MP7s, while the US Secret Service uses P90s. Advanced Armament Corporation (AAC), in cooperation with Remington, developed .300 Blackout in the late 2000s. AAC’s initial business was designing and manufacturing sound suppressors. Founder Kevin Brittingham was interested in a new round that would be extremely quiet from even a short barrel, suppressed AR-15 or M16-type gun, but still be reasonably powerful and accurate. Taking notes from earlier work on .30 caliber rounds for suppressed guns, AAC’s Research and Development Director Robert Silvers led the project that ultimately turned out the new cartridges AAC initially planned two basic versions, a supersonic type with ballistics similar to the old Soviet 7.62mm bullet used in the AKM, as well as a subsonic variant specifically for suppressed firearms. Today, independent suppliers offer multiple loads, with different bullets and powder charges, offering varying performance under certain conditions. To keep thing as simple as possible, .300 Blackout uses the same case head and taper as a military 5.56mm cartridge. This means you only need to change a AR-15 pattern gun’s barrel to accommodate the new ammunition and can use your existing magazines. No additional special parts are needed to swap between the supersonic and subsonic cartridges.

AAC The Honey Badger Low Visibility Carbine.