The Unique Bushmaster ARM Pistol: Historical Look

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I innocently strolled into the local shopping mall late on a Friday afternoon in August of 1984. It had been a brutal first week as a freshman Mechanical Engineering student, and I thought taking my girlfriend out for dinner and a movie would be just the ticket to lift our spirits and recharge our batteries. Corn Dog 7 did dinner. I still remember that their french fries were simply divine. The movie was some new action flick called Red Dawn. I knew nothing more about the movie than what I could glean from the poster outside the theater. I had no inkling the extraordinary experience that awaited me therein. Red Dawn was the world’s first PG13 movie. Crafted by John Milius, a token red-blooded patriotic conservative amidst an industry awash with pinko Leftists, Red Dawn became a movie genre unto itself. There’s really never been another film like it before or since. The Bad Guys were really bad, the Good Guys were really good, and the film just dripped raw unfiltered patriotism.

Throughout it all, Americans fought, sacrificed, and died defending Ronald Reagan’s America from the rampaging godless communist hordes. For a young patriot like me, Red Dawn was 114 minutes of steaming red meat. I left the theater that day ready to arm myself, snatch up my woman, head for the wilderness, and lead a covert insurgency defending my hometown against the vile commie menace.

A Different Time

It really is tough to visualize today what the 1980’s were really like for those who lived it. The hair was big, the music was loud, and the Gipper ably called the shots from the Oval Office. Reagan was naturally reviled by the Left, but his reassuring dulcet manner inspired confidence nonetheless. The Red Menace was the terrifying faceless enemy du jour. The Communists had sworn our destruction and crouched across the sea ready to rip our way of life from us by means of violence. Throughout it all the modern American gun culture was just beginning to germinate properly. The threat was quite real. Every single American lived downrange from some 45,000 Soviet nuclear warheads, and global thermonuclear war was never more than twenty minutes distant. Americans back then had sense enough not to burn their own cities down, but there yet remained uncertainty aplenty. This was the age of the survivalist. Prepping for the coming end of the world became a national pastime. As a result, it was a pretty good time to be making guns.

The Colt AR15 Sporter was just finding its legs in the 1980’s. The Ruger Mini-14 was a staple as well. There were no import bans so HK roller-locked rifles in 9mm, .223, and .308 were on the menu as were Uzi carbines, AUGs, and Galils if you had really deep pockets. Throughout it all, there was also a smattering of truly fascinating guns. The Holloway Arms Corporation HAC-7 was a short-lived though revolutionary 1980’s-era .308 battle rifle (see article in this issue). Stubby little MAC variants littered American gun shows. Until 1986, at least machineguns were also both cheap and plentiful. Polymer-framed pistols were rare, misunderstood, and up to that point skeptically received. However, one of the most remarkable 1980’s-era black guns was the Bushmaster Arm Pistol. The Arm Pistol remains arguably the most compact autoloading 5.56mm firearm ever devised.

The Arm Pistol began life as a proposed aircrew survival weapon, named the IMP, for the US Air Force chambered in .221 Fireball and in a bullpup configuration. However, after countless rounds burned and scads of taxpayer dollars invested, the USAF decided it apparently didn’t really need a new aircrew Personal Defense Weapon all that badly after all. That’s when Mack Gwinn of Gwinn Firearms, USA, took up the design.

The USAF Arm Pistol Becomes a Civilian

Mack Gwinn is the most influential gun guy you’ve likely never heard of. A Vietnam-era Special Forces veteran, Mack’s company Gwinn Firearms morphed into Bushmaster Firearms in the 1970’s. Bushmaster was eventually sold and went on to become one of the largest gun manufacturers in the country. Mack cut his teeth on the Arm Pistol. However, he also designed the M2 .50-caliber QCB (Quick Change Barrel) machinegun for FN and the 90-round drum magazines sold by the MWG Company back in the day. He created the MGI HYDRA modular carbine as well.

The transition to civilian sales, in the late 1970s, involved rechambering the Arm Pistol for the slightly-larger and more readily available .223 Remington round and incorporating as many AR15 parts as possible. This made the magazine release and fire controls seem familiar and cut down on costs. The rest of the gun, however, remained radically innovative. The action is a fascinating hybrid design. The operating system is piston-driven and inspired by the Kalashnikov. The action locks by means of a modified M16 rotating bolt system with a cam raceway machined into the wall of the aluminum upper receiver. The gun ejects out of the top of the action, while the pistol grip and flash suppressor are standard M16 components. The upper and lower receivers are cut from blocks of aluminum, while the remainder is steel. I’m told the original military guns were blackened stainless.

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A surprising lot of this weapon is standard AR15 to include the bolt, firing pin, and takedown pins. The bolt even retains its gas rings now rendered superfluous by the long stroke gas piston system. The fire controls are modified M16 components. In fact, the hammer and disconnector on my gun are of the stock full auto M16 sort. There is a trip lever attached to the modified M16 trigger that is manipulated by a spring-loaded actuator telescoping back from the primary trigger to fire the gun. There are reversible sling mounts front and rear. The charging handle is a stubby little steel appendage atop the receiver that cycles with the action. The trigger guard is a simple strip of flat steel.

Safeties came in three broad categories. The earliest consisted of a rotating lever akin to that of the AR15 located above the trigger assembly. There were purportedly very few of these made. My gun spawned from the second run wherein the safety was a sliding lever located ahead of the trigger within the trigger guard. This device can be readily manipulated by the trigger finger. The later guns had a rotating safety lever built into the rear of the weapon on the lower receiver.

Gwinn also adapted the same novel action and receiver to a conventional long gun chassis except that these rifles were not bullpups. These rifles sold alongside the Arm Pistol in periodicals like Shotgun News back in the day. There is a niche market in collecting these odd guns today. By 1984, the Arm Pistol had already been in commercial production for about six years. However, there weren’t so many black gun enthusiasts in circulation to buy such stuff back then, and the market wasn’t nearly so expansive as it is today.

I have read that there were only 2,100 Arm Pistols produced before the production run petered out around 1990. There were a few selective fire versions built before the 1986 ban that command quite a premium today as do all transferable full auto weapons. There was even a stainless-steel version. Semiauto Arm Pistols can be found via online gun auctions running between $1,800 and $3,000 as of this writing. For all its simply breathtaking innovation, however, the Arm Pistol remained fatally flawed.

Practical Tactical

The Bushmaster Arm Pistol wants so badly to be awesome. Just sitting on the bench, it looks like the coolest thing since the flush toilet. However, looks can certainly be deceiving. The Arm Pistol ejects out the top with substantial vigor. To compensate for this the action pivots through about thirty degrees on either side of the centerline. As such the magazine rests against the inside of the forearm and naturally directs ejection away from the shooter. This pivoting action only affects the pistol grip and trigger, however. The rest of the chassis remains rigidly aligned. That aspect of the design is legitimately inspired.

The folks who designed the Arm Pistol were heavily influenced by combat experiences during World War 2. Back then hip shooting was a real thing. Nowadays we obviously pretty much fire accurately from the shoulder or not at all. Back then, however, spraying rounds from the hip was a recognized way to break contact or suppress an ambush. The Arm Pistol reflects this relatively archaic ethos.

The Arm Pistol may indeed be fired comfortably one-handed from the hip. Conversely the weak hand may be used to stabilize the gun by grasping the magazine. In my gun at least with the sliding safety inside the trigger guard the weapon’s controls are easily managed. So far so good. Where things fall apart is when you try to wrest any degree of precision from the gun. There is a fixed steel sight up front and a corresponding notch at the rear. However, both are completely occluded by the solid steel charging handle and are therefore rendered utterly worthless. My gun has a notch ground into the top left aspect of the rear sling attachment point. This small notch can technically be aligned with the top left corner of the front sling slot for use as a rudimentary sighting system. However, this rig is in no way adjustable and remains profoundly difficult to use.

You want to pull the gun into your shoulder and rest your face against the side of the receiver. However, in this configuration the charging handle is slamming back and forth maybe half an inch from your eyes and throwing out hot brass as fast as you can squeeze the trigger. I’m honestly not man enough to try that for real. The best way I have found to actually aim the gun is to hold the arm outstretched with the weapon supported against the strong forearm by the weak hand. Be advised, however, that this is akin to wearing a tutu in a biker bar. It’s tough to hit anything, and it neither looks nor feels natural. All that negative stuff notwithstanding, the gun carries wonderfully. A downed aviator isn’t trying to fight his way into some evil lair to rescue the Dallas Cowboys Cheerleaders. He just wants to remain sufficiently prickly as to keep the Bad Guys at bay long enough for help to arrive. In that regard the noisy little Arm Gun, area weapon system that it is, would yet remain fairly effective.

Applications

In a 1980’s civilian context the Bushmaster Arm Pistol would be a truck gun. If the balloon went up while you were off at a Def Leppard concert or watching a space shuttle launch this is the gun that would help you fight your way back to your survivalist enclave. This mission is actually fairly similar to what the Air Force originally designed the gun for anyway. When this gun was being actively marketed, Dirty Harry was still blasting his way across the silver screen. American shooters were subsequently caught up in the relentless pursuit of ever-greater handheld firepower. This odd little domestic arms race was driven by the flawed narrative that bigger was better. If a massive wheelgun that packed six .44 Magnum rounds was good, then a comparably-sized pistol carrying thirty rounds of 5.56 must be even better.

Those of us who actually bought these guns fell for the sexy chassis and the nifty lines. After throwing a few live rounds downrange the luster is pretty much gone. This is the weapon that will impress first-time visitors to the gun safe. However, it wouldn’t be my first choice to rescue Farrah Fawcett and Christy Brinkley from Hans Gruber at Nakatomi Plaza. (If you haven’t seen Die Hard, and both of you know who you are, then that last bit admittedly doesn’t make a lick of sense).

I recall seeing a few of these weird little weapons at gun shows back in the day. It was not terribly unusual to see them outfitted with extended CAR-15 flash suppressors. This was to help shield you from all that muzzle chaos exploding mere inches from your nose. I once had a phone conversation with Irv Kahn, a prolific 1980’s-era Class 3 dealer, about the full auto version of the Arm Pistol. He had two in stock at the time for $1,000 apiece. Alas, for a starving college student with a girlfriend addiction they might just as well have been on Mars. That’s OK considering running one of these odd little guns on full auto would be like riding an angry rhinoceros bareback while on fire. So, what’s the Arm Pistol really good for? Not a great deal it turns out. It would, however, indeed make a handy truck gun.

The Arm Pistol is sufficiently tidy as to hide comfortably behind the seat in the family minivan. It would be the rare Antifa loser who would press home an attack against a determined soccer mom thusly equipped. However, if you actually had to connect with a specific target when friendlies were about that would likely become an insurmountable challenge. What the Arm Pistol truly excelled at was just being cool. This was arguably the first military weapon to hybridize the good stuff from the AR-15 and meld it with the rugged Kalashnikov operating system. That is commonplace these days, but it was pretty radical stuff back in 1972. Back then there were not a great many Americans who had ever even seen an AK up close, much less had opportunity to study one in detail.

Had the Arm Pistol been designed today, there would be mounts for a red dot and a tactical light. Were someone smarter than I to rethink the ejection system, this could become a truly game-changing firearm. As it is the Bushmaster Arm Pistol remains little more than a curious novelty — a throwback to a weird time when the hair was big, the music was loud, Reagan called the shots, and nuclear annihilation was never more than half an hour away.

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About the Author

Will is a mechanical engineer who flew UH1H, OH58A/C, CH47D and AH1S aircraft as an Army Aviator. He is airborne and scuba qualified and summited Mount McKinley, Alaska, six times…at the controls of an Army helicopter. After eight years in the Regular Army, Major Dabbs attended medical school. He works in his urgent care clinic, shares a business building precision rifles and sound suppressors, and has written for the gun press since 1989.

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