The machine gun changed warfare, causing the marching formations of the Civil War to give way to the industrialized warfare of World War I. And the U.S. has fielded dozens of designs since Hiram Maxim first tried to interest the country in his 1884 design. Here are six of the best.
For this list, we're using a definition of machine gun limited to fully automatic weapons, so the hand-cranked Gatling Gun of 1862 is out, but automatic weapons with a rifled barrel like the Browning Automatic Rifle are in.
1. Maxim Machine Gun
Hiram Maxim sits with the machine gun he invented. (Photo: Public Domain)
The Maxim Machine Gun was invented in 1884 and was the first proper machine gun in the world. Hiram S. Maxim figured out how to use the recoil of one round firing to cycle a weapon and feed a new cartridge into the weapon's chamber. For 30 years, the weapon was tested by world governments, though not many were purchased.
It was in World War I that the weapon became famous as governments bought the Maxim and its copies and derivatives like the Lewis and Vickers machine guns. The Germans and Russians ordered their own versions as well.
2. Browning M1917
(Photo: U.S. Marine Corps)
Another Browning invention, the M1917 was a rushed but solid design to give the U.S. military a homegrown machine gun after its late entry into World War I. It was heavy, requiring a four-man crew. But it could fire up to 600 rounds per minute and was extremely reliable. In one test, it fired 20,000 rounds without a single malfunction.
Approximately 40,000 M1917s, all chambered for a .30-06 round, were sold during the war, but not all of them reached France.
3. Browning Automatic Rifle
A U.S. Marine fires the Browning Automatic Rifle in World War II. (Photo: U.S. Archives)
The Browning Automatic Rifle was so popular that, while it was designed for and fielded in World War I, American infantryman were loathe to give it up when it was replaced during Vietnam. It fired .30-06 rounds at nearly 2,700 ft. per second, enough force to pierce a light tank in World War I. And it could spit those rounds at up to 550 rounds per minute.
It's rifled barrel also made it very accurate, allowing infantryman to use it in an anti-sniper role. The inventor, John Browning, even had a son who carried it into battle in World War I, Army 2nd Lt. Val Browning.
4. M2 Browning Machine Gun
Marines with Company A, Infantry Training Battalion, School of Infantry-West (SOI-West), fire the M2A1 .50 caliber heavy machine gun as part of their basic infantry training Sept. 20, 2016, at Marine Corps Base Camp Pendleton, California. (Photo: U.S. Marine Corps Lance Cpl. Joseph A. Prado)
Originally designed in 1918 and produced in 1921, the M2 Browning Machine Gun is one of the longest-serving and most-loved weapons in history. It's reliable and fires .50-caliber rounds at over 2,700 ft. per second.
The weapons are so durable in fact, that in 2015 the Army found a 94-year-old M2 still in service. The weapon has undergone few upgrades and is still widely used. It's been mounted on everything from small vehicles to bunkers to aircraft.
5. M1 Thompson Submachine Gun
Two Marines from the 2nd Battalion, 1st Marine Regiment during fighting at Wana Ridge during the Battle of Okinawa, May 1945. (Photo: Staff Sergent Walter F. Kleine)
The first machine gun built as a pistol, the M1921 Thompson Submachine Gun was designed for trench warfare in World War I, but the conflict ended without real interest from the military. The M1, a simplified version, was delivered in World War II.
It gave the average infantryman the chance to fire a slew of .45-cal. rounds at enemy forces — though it was only effective at relatively short ranges. The military turned to the M3 in 1944, but the quality of the M1 saw it continue to serve through Vietnam.
6. M134 Minigun
(Photo: Department of Defense Shane T. McCoy)
The M134 Minigun is a massive weapon that fires relatively small rounds, 7.62mm cartridges. And it requires electrical power instead of relying solely on recoil or recycled gasses like the rest of the weapons on this list. But it fires its rounds faster than anything else on this list.
The minigun features a magazine of up to 4,000 rounds but can tear through those at 50 rounds per second, firing them from six barrels that rotate thanks to a 24-volt battery or vehicle power. These were the guns fitted to the AC-47, the first "Spooky" gunships, but the Air Force knew it as the GAU-2/A.