Machine Guns and How They Changed Combat: The Complete History (2026)

Last updated March 18th 2026

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Machine Guns and How They Changed Combat

The machine gun is the most consequential infantry weapon in the history of warfare. Nothing else even comes close. Before the machine gun, battles were decided by massed formations of soldiers trading volleys. After the machine gun, those formations were suicide. Every major tactical innovation of the 20th century, from trench warfare to blitzkrieg to modern combined-arms doctrine, was fundamentally a response to the problem of the machine gun.

This guide covers the major machine guns that shaped combat history, from the Gatling Gun through the Maxim, the Browning M2, and into modern squad automatic weapons. For the broader story of firearms in warfare, see our firearms in warfare guide. For the guns that changed the world beyond just machine guns, see our 14 guns that changed the world.

The Gatling Gun (1862): The Idea Takes Shape

Richard Gatling invented the Gatling Gun in 1862, ostensibly to “reduce the size of armies and so reduce the number of deaths by combat.” The irony of that statement has aged poorly. The Gatling was a hand-cranked, multi-barrel weapon capable of roughly 200 rounds per minute. It saw limited use in the American Civil War, was more widely deployed in the Indian Wars and colonial conflicts, and proved that sustained rapid fire was militarily viable.

The Gatling wasn’t a true automatic weapon (it required the operator to continuously crank the handle), but it established the concept. The idea that a single weapon could do the work of dozens of riflemen was proven, and that idea would lead directly to the weapon that changed everything.

The Maxim Gun (1884): The Weapon That Changed Everything

Hiram Maxim’s machine gun was the first fully automatic, recoil-operated weapon. Pull the trigger, and it kept firing at 600 rounds per minute until you released it or ran out of ammunition. It was water-cooled (giving it sustained fire capability), belt-fed, and devastatingly reliable. It was also heavy, required a crew of 4 to 6 men, and needed water and ammunition supplied in quantity.

The Maxim’s impact was felt most brutally in the Colonial Wars of the late 19th century, where small European forces armed with Maxim guns defeated vastly larger indigenous armies. At the Battle of Omdurman (1898), British forces with Maxim guns killed an estimated 10,000 Sudanese warriors while suffering fewer than 50 deaths. The phrase “Whatever happens, we have got the Maxim gun, and they have not” captured the grotesque asymmetry of the technology.

Then came World War I, and the Maxim (and its derivatives like the German MG 08 and the British Vickers) turned the Western Front into a killing ground. Machine guns in entrenched defensive positions could destroy attacking infantry at hundreds of yards. The result was four years of trench warfare, millions of casualties, and a fundamental rethinking of how wars are fought.

The Lewis Gun and BAR: Portable Firepower (WWI-WWII)

The Maxim was devastating but immobile. The next evolution was making automatic weapons portable enough for an individual soldier to carry and fire on the move.

The Lewis Gun, an air-cooled, magazine-fed light machine gun, gave infantry units their own automatic firepower without needing a dedicated crew-served weapon. It saw extensive use in World War I on both the ground and in aircraft. John Browning’s Browning Automatic Rifle (BAR) took this further: at roughly 16 pounds, the BAR gave a single infantryman the ability to provide suppressive fire while advancing. The concept of “walking fire” (soldiers advancing while laying down automatic fire) was born with the BAR, and it served from WWI through the Korean War.

The Browning M2 .50 Cal: 90+ Years and Counting

John Browning designed the M2 heavy machine gun in the late 1910s, and it entered service in 1933. It’s still in active military service today. That’s not a modified version or an “inspired by” successor. The same fundamental design, firing the same .50 BMG cartridge Browning also created, from the same operating mechanism. No other weapon system in history has served this long without a fundamental redesign.

The “Ma Deuce” fires .50 BMG rounds at 450 to 600 rounds per minute. It’s effective against vehicles, light armor, aircraft, buildings, and personnel out to nearly 2,000 yards. It’s been mounted on tanks, trucks, ships, aircraft, and tripods in every American conflict since World War II. The M2 is the reason the .50 BMG cartridge exists, and civilians can own semi-automatic rifles chambered in it. See our best .50 BMG rifles, Barrett rifles, and best .50 BMG ammo guides.

The MG 42: Hitler’s Buzzsaw

The German MG 42 of World War II is widely considered the best machine gun ever made. Its cyclic rate of 1,200 rounds per minute (20 rounds per second) was so fast that individual shots blended into a continuous ripping sound, earning it the nickname “Hitler’s Buzzsaw” from Allied soldiers. It was air-cooled with a quick-change barrel system, belt-fed, and light enough to be used as both a squad automatic weapon and a medium machine gun on a tripod.

The MG 42 was so effective that the US Army studied it extensively after the war. Its design directly influenced the M60 machine gun and, through the MG 3 (a post-war variant), it’s still in use with several NATO armies today. The concept of the “general-purpose machine gun” (one weapon system that serves both the light and medium roles) began with the MG 42.

Modern Squad Automatic Weapons: M249 SAW and Beyond

The M249 SAW (Squad Automatic Weapon) has been the standard US infantry squad machine gun since 1984. Chambered in 5.56 NATO (the same cartridge as the M4/M16), it provides suppressive fire at the squad level with a belt-fed, 200-round box capacity and a cyclic rate of 750 to 1,000 rpm. It’s light enough (17 pounds) for one soldier to carry and fire, though it’s heavy enough that the SAW gunner is always the most tired person in the squad.

The US Army’s NGSW program is replacing the M249 with the Sig Sauer XM250 in 6.8x51mm, a more powerful cartridge designed to defeat modern body armor. Whether this new platform proves as durable and effective as the M249 remains to be seen. For how military procurement works, see our military procurement guide.

Can Civilians Own Machine Guns?

Under the National Firearms Act, machine guns manufactured and registered before May 19, 1986, can be legally owned by civilians with an NFA tax stamp. These “pre-86 transferable” machine guns are rare and expensive: $30,000 to $50,000+ for a transferable M16, and similar prices for other popular models. Machine guns manufactured after 1986 are completely banned from civilian ownership under the Hughes Amendment.

For civilians who want the experience without the six-figure price tag, many ranges offer machine gun rentals, and there are machine gun shoots and events throughout the country. For the semi-automatic rifles that share the platforms with military machine guns, see our best AR-15 rifles and best AK-47 rifles guides. And for understanding the full spectrum of military vs civilian firearms, we have a dedicated guide.

Related Guides

• How Firearms Changed Warfare
• The History of Firearms
• 14 Guns That Changed the World
• John Moses Browning: Life & Legacy
• Military vs Civilian Firearms
• What Is the National Firearms Act?
• Most Popular Military Small Arms
• Best Military Sniper Rifles
• 10 Best .50 BMG Rifles
• How the Military Buys Its Guns

The Bottom Line

From the hand-cranked Gatling to the M2 .50 cal that’s been in service for over 90 years, machine guns have defined modern warfare more than any other single category of weapon. They created trench warfare, forced the development of tanks and combined-arms tactics, and remain the backbone of infantry firepower. The machine gun didn’t just change how wars are fought. It changed whether wars could be won at all by forces that lacked them.

FAQ: Machine Guns in Combat