The HELL of M134 Minigun

Added: 2026-05-10

[00:00:00]If I told you that one of the most effective weapons today that fires 6,000 rounds per minute is based on a concept from 1862, you'd probably think I'm crazy. And I might be crazy. That's another topic. But not for this. In the middle of the 19th century, infantry combat was still stuck on slow muzzle loading rifles. And even a well-trained soldier could fire only about two or three aimed rounds per minute. The American Civil War was causing heavy casualties and both sides were desperate for ways to increase the volume of fire without simply bunching up more rifles and more men who were going to die anyway. And the answer would come from, of all people, a doctor. Richard Jordan Gatling was actually struck by the fact that more men were dying of disease in camp than from the fighting itself. And his almost humanitarian logic was that if one man with the right weapon could do the work of a hundred, armies could be smaller, wars could be shorter, and fewer men would die of disease. So he set out to quote unquote fix that by inventing a far deadlier weapon, which by a weird twist of events gave us a gun concept that's still used today over 160 years later. Just not in the way Gatling could have ever imagined. You see, the Gatling gun used a cluster of six or as many as 10 barrels arranged around a central shaft rotated manually by a hand crank. As the operator turned the handle, the barrels passed through a complete cycle where a cartridge was dropped into the brereech from a gravity-fed hopper or a magazine at the top. A cam-driven mechanism then chambered and fired it. And as the barrel continued downward, the spent casing was extracted and ejected out the bottom. And all of this was a purely mechanical process without a gas system or anything like that. Basically like if you'd put six boltaction rifles together and then by turning them around made their bolts work and fire the rounds. In simple words, that's how the Gatling's design worked. This allowed the early six barrel versions to fire up to 200 rounds per minute when soldiers were happy with anything more than three. And by the way, the whole rotating mechanism was actually inspired by a seed planter Gatling had built years earlier, back when he was working as an agricultural inventor before he ever moved into weapons. His gun would later be refined into newer models that could fire up to 400 rounds per minute in field conditions. But what does that have to do with the minigun and our topic today?

[00:02:16]Well, one of the things that Gatling had was that by spreading the fire across many barrels, no single barrel had to absorb all the heat. And by automating the feed with cams, the gun could fire at a rate no single rifleman could approach, which would turn out also to be true later when the real machine guns came. But bear with me for a moment.

[00:02:36]However, in 1883, a guy named Hyram Maxim came along with his fully automatic singlebarrel recoil operated water cooled machine gun, which changed everything and pushed the Gatling gun aside completely. It was way lighter, beltfed, didn't need any hand cranking or a large crew, all while easily exceeding the Gatling gun's rate of fire. So, it didn't take long before guns based on Maxim's principle fully replaced the Gatling's concept. But while his concept was being pushed aside, Gatling himself was experimenting with something new. He fitted an electric motor to his gun to replace the hand crank and push the rate of fire to somewhere between 1500 and 3,000 rounds per minute when fired in short bursts.

[00:03:17]Now, keep in mind this was over 130 years ago, but the electric motor technology of the era was just too unreliable, and the experiment was shelved as a curiosity for now. Now, the Gatling gun was declared obsolete in 1911, and the multiarrel rotary concept appeared to be a dead end throughout two World Wars. That was until a completely new problem showed up that no machine gun in the world could solve. You see, during World War II, fighter planes ran on piston engines and propellers. They were armed with heavy machine guns and autoc cannons that worked pretty well for dog fights at those speeds. But then jet fighters were introduced in the years after the war and the nature of dog fighting changed completely. They were now so much faster and would literally flash through your gun site in a fraction of a second. So if you wanted to hit an enemy fighter in a dog fight, your guns had to put out as many rounds as possible in that tiny window.

[00:04:09]Engineers were banging their heads against the wall over this one because they hit the limit of pushing the rate of fire of existing machine guns and autoc cannons without solving the problem. They also tried to put more weapons on fighters to multiply the firepower. But that limit was hit as well. And they just couldn't find the right solution for the problem. But as it turned out, the answer to all this was sitting in a museum the whole time.

[00:04:30]You see, two army officers got the idea to test the old Gatling gun with an external electric motor to really push the rate of fire through the roof, which is the same thing Gatling himself experimented with a while back. They mounted the motor on the hand crank, loaded the thing up, and fired it. The results were just shocking. The 60-year-old Civil War design briefly managed to fire at a rate over 5,000 rounds per minute, which was unheard of.

[00:04:54]Apart from the huge black clouds of smoke from the old ammo they used, the test was a complete success. This was exactly what they were looking for. Now, General Electric took over the development in what was called Project Vulcan, where they wanted a sixbarrel weapon firing over 7,000 rounds per minute. They were also searching for the right round with the best balance of weight, explosive power, and muzzle velocity, and eventually went with a 20 mm round. There were a bunch of problems at first, as the linked ammunition caused feeding problems, and the ejected links scattered inside the aircraft, which was a serious safety hazard. But this was solved with a linkless ammunition feed system. And the weapon they eventually came up with was standardized and designated as the M61 Vulcan, a rotary 20 mm cannon for jet fighters. It fired at a rate of 6,000 rounds per minute, which when you do the math is 100 rounds per second, and now finally solved that gap in firepower. So the Vulcan was mounted on F105 Thunder Chiefs and F4 Phantoms. And by Vietnam, it proved very effective in dog fights against Soviet-built MiGs. Now, with the Vulcan proving the concept, the army wondered if they could scale this thing down for platforms where the Vulcan would be too big or heavy, like helicopters, light aircraft, small boats, and even ground vehicles. They started working on it, and by 1962, General Electric came up with a 7.62x 62x 51 mm NATO 6barrel machine gun that could also fire 6,000 rounds per minute, just like its big brother. It entered service the next year under the designation M134 minigun. If you've ever seen one of these before, you'd know that it's hardly mini. But when you compare it to the Vulcan as its predecessor, the name makes more sense.

[00:06:35]And while the minigun is not exactly the scariest name you could pick for a weapon, field use would show otherwise.

[00:06:42]Its first and most important job was to help in defending outposts in the Vietnam War that were getting attacked by guerilla fighters at night and a bunch of them got overrun. The only air support ground troops in Vietnam had at the time were jet fighters. But they were not the right solution for this problem. Their night capability was poor. They didn't carry a lot of ammo and they were made to be extremely fast and nimble for dog fights or strafing runs where they'd fire just in short bursts at the target before flying off.

[00:07:09]They then had to reposition again for a strafing run, and by that time, the guerillas had already gotten into cover or change their position. A fighter jet simply wasn't built to circle around the outpost the whole night and provide constant ground support to forces under attack. The best ground forces could get was old World War II era C47 sky trains, dropping flares at night to illuminate the attackers. But that was far from what they actually needed to defend surrounded outposts from VC ambushes.

[00:07:36]But then Captain Ron Terry jumps into this story. He advocated for that sidefiring concept that was ignored since the 1920s as some weird experimental idea, but it was actually really ingenious. This guy somehow barely convinced the big heads in the military to let him mount three miniguns onto that C47 that was just dropping flares and then while the plane was flying in the so-called pylon turn to fire the guns from the side at ground targets. So Terry and his team mounted three M134 miniguns on the left side of the gunship's cargo compartment, one in the cargo door and two in the rear windows. The trigger was placed on the pilot's control yolk, and he could fire them either individually or all at once at two selectable rates of either 3,000 or 6,000 rounds per minute each. With all three firing at the higher rate, they could place a round into every square yard of a football field-sized area in just over 10 seconds, all from 3,000 ft in the air. The first modified gunship was ready under the designation FC47, and it was now time to test it.

[00:08:37]Now, when the VC pressed attacks against a couple of outposts in South Vietnam, they saw the flare ship and took cover, expecting it to pass like it always did.

[00:08:45]Only this time, it was more than just flares as three miniguns opened up on them, fired 5,000 rounds in just a few seconds, and completely broke the attack. The gunship then flew to the second surrounded outpost, 20 mi away, and did the exact same thing again. So now the concept was proven and the US Army started adding M134 miniguns to refurbished C47s taken from boneyards and 20 of them were sent to Vietnam by November 1965. The designation was changed from FC47 to AC47 for attack as fighter pilots found it offensive to call a slow World War II transport aircraft a fighter. But troops got even more inspiration when coming up with nicknames. So, a better known nickname was Spooky, which was the call sign they used for the gunship over the radio. But perhaps the most colorful nickname it got was Puff the magic dragon because it could fire up to 300 rounds per second and every fifth round was a red tracer.

[00:09:42]So, it looked like a continuous glowing red stream which looked like a dragon's breath. I've never seen a dragon's breath, but that's how they described it. So, armed with three miniguns, not a single outpost was overrun while Spooky was orbiting above. Meanwhile, the minigun had found its way to helicopters as well. The Belleu H1 helicopters, which you might better know as Hueies, were the workhorse of the Vietnam War.

[00:10:05]But in the beginning of the conflict, they flew unarmed, which unsurprisingly resulted in quite the horrific losses.

[00:10:11]They then added M60 machine guns, but one or two M60s firing at some 600 rounds per minute weren't the best weapon in the world for a helicopter to break ambushes in hot landing zones and even support ground troops in trouble.

[00:10:24]Although the M60 would still be used quite a lot, but they really needed to concentrate more firepower at the landing area while the troops were dismounting. And naturally, they tested the M134 minigun as the door gunner's weapon. And you can pretty much guess what that looked like with 10 times more firepower than the M60. But there's also one more thing with the minigun mounted on helicopters. The rotary barrels vibrate slightly during firing, which spreads the rounds over a wider area instead of concentrating them on a single spot. Since the Americans rarely knew exactly where the VC were hiding, covering a wider area with more firepower was a huge advantage for suppressing them. Some Hueies mounted miniguns in door mounts, while others were converted into gunship variants with miniguns fixed in side pods or chin turrets that were aimed by the pilot.

[00:11:10]The rate of fire was reduced from 6,000 rounds per minute to two selectable rates of either 4,000 or 2,000 because the helicopter couldn't really carry that much ammo, so they had to fire in short bursts. So, with the concept working this well, they took it even further and created the first ever purpose-built attack helicopter, which you might know as the AH1G Cobra. Now, there were many different weapon variations for the Cobra, but the most common was the Chin turret with a single M134 minigun with 8,000 rounds paired with a 40mm grenade launcher. The turret was aimed by the front seat gunner, while the stub wings carried twin rocket pods for explosive power. There were also all gun configurations with up to six miniguns mounted for specific roles with two in the nose and two on each wing, but it wasn't that common, mostly due to ammo consumption. Later versions replaced the M134 minigun with a bigger threebarrel 20 mm rotary cannon similar to the Vulcan, which pretty much ended the M134 minigun service for Cobra helicopters. Now, one platform that actually kept the minigun in service for long after Vietnam was Navy riverine patrol boats. You see, the US Navy was operating on narrow rivers in Vietnam with dense jungle pressed up against both banks, which was perfect ambush terrain. A boat could be hit from anywhere at any moment. And the same concept of saturating a wider area with fire worked perfectly here as well. The miniguns stayed on those boats long after the war ended. And while it didn't fully disappear after Vietnam, the miniguns role narrowed down quite a bit.

[00:12:45]The US had about 10,000 miniguns during the war and now they couldn't find a purpose for most of them. Many were being stored away or scrapped.

[00:12:52]Throughout the 70s and 80s, the remaining miniguns stayed in use, but they were wearing out badly. Fast urgent wartime production combined with years of heavy use had put a serious strain on their feeding systems, which kept jamming and malfunctioning. However, then came the 1990s and with them a very unexpected chain of events. A man named Mike Dylan used a couple of miniguns for a movie shoot and the guns just kept jamming so much that they couldn't even film the scene they wanted. He got so annoyed that he decided to take them apart and see what was wrong. The thing was that Dylan ran a reloading equipment company, so he had a whole team and all the tools he needed to do the job himself. They discovered that most problems came from the feeding system.

[00:13:33]So they redesigned it and created a completely new one. It was far smoother, easier to maintain, and much easier to fix if something went wrong again. With these adjustments, the system was now far more reliable, and it caught the attention of the army's 161st Special Operations Aviation Regiment, the elite unit known as Nightstalkers. They used miniguns for their helicopter operations, and a new improved version was just what they needed. Dylan's team showed it to them on the firing range, and they loved it. They started buying them and so Dylan kept improving everything on the minigun he thought could be made better. Basically rebuilding the weapon piece by piece. In the early 2000s, he built a completely new minigun from scratch, which the military was excited to buy. The new version had a fixed rate of fire of 3,000 rounds per minute instead of selectable speeds, which simplified the whole system. It was lighter, cheaper to produce, far more reliable, and now officially approved as the M134D.

[00:14:29]It spread quickly, replacing older versions on helicopters and boats. And the army even tested it on military Humvees and ground vehicles in Iraq, which scared the life out of the enemy fighters. And I'm not just saying that it scared them. Soldiers that didn't have miniguns on their Humvees actually started mounting fake barrels made from painted PVC pipes, which worked almost like the real minigun to scare off the enemy. And special units did quite the opposite. They were hiding their miniguns so the enemy would think they were easy targets and attack. And well, you can imagine what would happen then.

[00:15:01]By now, over 6,000 M134D miniguns have been produced sitting on helicopters, boats, gunships, and ground vehicles all around the world. And the whole thing traces back to a doctor in the 1860s who came up with the idea to shorten wars and save lives, which is like a lot of ideas in military history, not exactly working out how someone imagined