I love weird guns and weird gun genres. Today is all about the arm pistol. Arguably, the arm pistol as a genre barely exists. The only three purpose-built arm pistols I can find were only ever prototypes. Beyond that, there is a still unreleased conversion kit, a French design that exists only as a drawing, and some imagination. I could argue that every gun with a pistol brace is an arm pistol, but I don’t think that’s fair. Let’s dissect arm pistols, and maybe we’ll figure out why none exist. (But one kind of does)
What’s Are Arm Pistols
It’s important that I use the term pistol, but in reality, an arm pistol could be a submachine gun. It’s typically stockless, and arm pistols better describe these guns as a whole. There is plenty of room to argue it’s not a pistol, and that’s fine. An arm pistol is a gun that is larger than your typical handgun and typically functions differently than a normal handgun. They tend to rest on the arm in one way or another to provide greater stability.
Yep, just like an arm brace. The difference lies in intent. A braced pistol was intended to be shouldered, but the NFA makes adding a stock difficult, so the best we can do is brace it to our forearms. Arm pistols were designed to be braced against the arm from the very beginning. These guns lacked the stock to keep the weapon as compact as possible.
These guns can be used at ranges beyond a typical handgun but well below a rifle. Their small size allows for easier storage and better close-range use. These weapons are also bullpups by design, further reducing size.
Arm Pistols – The Examples
The definition of an armed pistol and the entire genre comes down to three guns. Colt developed the first Arm Pistol and called it the Individual Multi-Purpose Weapon, or IMP. Colt designed the IMP to be a survival weapon for aircrew. The IMP started by chambering the .221 Remington Fireball, but later, a proprietary .221-17 IMP caliber was produced for the military.
The gun did not have a stock and sat along the forearm. The rear of the weapon could pivot left or right to rest alongside the gun while allowing the user to grab the pistol grip. Five prototypes were produced, but the program was canceled.
The Bushmaster Arm pistol is the second and most prominent arm pistol. The original Bushmaster, or Gwinn Arm pistol, came to be after Mack Gwinn acquired the rights to the Colt IMP. He developed the Bushmaster Arm Gun.
The Bushmaster version chambered the 5.56 round and used AR-15 magazines. It produced limited numbers in both semi-auto-only and select-fire models. Hydra Weaponry has recently brought the gun back for a limited production run. Mach Gwinn Jr. owns Hydra and is bringing back his father’s gun for modern collectors.
In 1970, Donald Stoehr created the prototype Stoehr Machine Pistol, which was quite interesting in its design. It’s a blow-forward, fully automatic machine pistol. The gun rests on the forearm, and the magazine sits offset from the sights. The magazine is a pan magazine that holds a metallic tape belt that holds the cartridges.
Modern Options
Beyond the actual prototypes, the closest thing we have in the modern era is the JTAC L1 Stribog Bullpup Lower. It converts a Stribog large format pistol into a bullpup pistol without a brace or stock. Sadly, the kits have been in development for years but have yet to hit the market.
Generally, any modern arm pistol will be a novelty or reproduction like the Hydra Weaponry variants. Braces define the contemporary era of oddly large pistols. This genre had a brief history and its rise and fall. It’s a tiny genre of weapons that never really went anywhere. It’s neat but difficult to shoot accurately, difficult to control, and ultimately not all that effective.
These guns are neat, and boy, oh boy, do I want to get my hands on a Hydra Weaponry model, but they aren’t all that effective. At the very least, their effectiveness hasn’t been fully embraced. I’d love to try a more modern example with a red dot and maybe apply the cheek pistol concept. Maybe one day, but for now, arm pistols are a weird gun genre that’s dead.
