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

Last updated March 2026 · By Nick Hall, firearm historian covering machine gun development from the Gatling through modern M240

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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.

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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.

What’s interesting is that military leadership was slow to recognize the Gatling’s potential. Many Civil War generals saw it as a novelty or a siege weapon, not a field tool. It took colonial warfare, where small European detachments used Gatlings against numerically superior forces, to demonstrate what concentrated automatic fire could really do.

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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.

The Maxim didn’t just change individual battles. It changed the entire calculus of colonial power. A handful of soldiers with a Maxim could hold territory that previously required a garrison. It made European expansion cheaper in blood (for the Europeans), and it made resistance by indigenous populations with traditional weapons functionally hopeless. The political and moral implications of that asymmetry still echo today.

The Maxim’s Children: WWI and the Trenches

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. A single well-placed machine gun crew could hold off an entire battalion. The result was four years of trench warfare, millions of casualties, and a fundamental rethinking of how wars are fought.

The numbers are staggering. On the first day of the Battle of the Somme (July 1, 1916), the British Army suffered nearly 60,000 casualties, the majority from machine gun fire as soldiers walked across open ground toward German positions. Generals kept ordering these attacks because they had no doctrine for dealing with entrenched automatic weapons. The entire war on the Western Front was essentially four years of trying to solve the machine gun problem.

The solutions that eventually emerged (tanks, infiltration tactics, combined-arms coordination, creeping artillery barrages) all trace back to one fundamental issue: how do you advance against a weapon that can kill hundreds of men per minute? Every tactical innovation of the 20th century has roots in that question.

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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. The top-mounted pan magazine held 47 or 97 rounds, and while the gun was heavy at 28 pounds, one soldier could carry and operate it. British infantry sections built their entire tactical approach around the Lewis Gun, with the rest of the squad supporting and protecting the gunner.

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. It wasn’t perfect. The 20-round magazine was too small for a sustained support role, and it was too heavy for a standard rifle. But it filled a gap that nothing else could, and it served from WWI through the Korean War.

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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.

What makes the M2 so remarkable is its versatility. In WWII, it served as an anti-aircraft weapon, a ground support weapon, a vehicle-mounted weapon, and even an improvised sniper rifle (Carlos Hathcock famously used a scoped M2 in Vietnam to achieve kills at over 2,000 yards). There have been attempts to replace it over the decades. None have succeeded. The M2 just works, and 90 years of combat service is the ultimate proof of concept.

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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 built around a concept the Germans called the “Einheitsmaschinengewehr” or universal machine gun. One gun, two roles. Mounted on a bipod with a 50-round belt, it served as a squad light machine gun. Put it on a tripod with a 250-round belt and an optical sight, and it became a medium machine gun capable of sustained defensive fire. This flexibility meant German squads were built around the machine gun, with riflemen supporting the MG 42 gunner rather than the other way around.

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 chambered in 7.62 NATO), 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 and remains the standard approach for most modern militaries.

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The M60 and the Vietnam Era

The M60, America’s general-purpose machine gun from the late 1950s through the 1990s, drew heavily from the MG 42’s design (and the FG 42 rifle). Chambered in 7.62 NATO, the “Pig” (as soldiers called it) was the squad’s base of fire in Vietnam and beyond. At 23 pounds, it was heavy but manageable for one soldier, and it gave American infantry units serious suppressive firepower at ranges beyond what the M16 could deliver.

The M60 had reliability issues that frustrated the soldiers who carried it. Feed problems, a tendency for the barrel to come loose, and parts that wore quickly in jungle conditions made it a love-hate relationship for most M60 gunners. But when it worked, it was devastating. The sound of an M60 opening up became one of the defining sounds of the Vietnam War, and it served as the standard US medium machine gun for decades before being replaced by the M240.

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Modern Squad Automatic Weapons: M249, M240, 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 M240 (based on the FN MAG, a Belgian design) replaced the M60 as the medium machine gun. Chambered in 7.62 NATO, the M240 is heavier at 27 pounds but dramatically more reliable than the M60 it replaced. It’s the company-level machine gun, providing sustained suppressive fire at longer ranges than the M249. Between the M249 and M240, a modern US infantry platoon has automatic firepower at both the squad and platoon level, covering everything from close-range suppression to ranged fire support.

The US Army’s NGSW program is now replacing the M249 with the Sig Sauer XM250 in 6.8x51mm, a more powerful cartridge designed to defeat modern body armor at extended ranges. The XM250 is lighter than the M249 while firing a harder-hitting round. Whether this new platform proves as durable and effective as the M249 over decades of service remains to be seen. For how military procurement works, see our military procurement guide.

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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 ($200). These “pre-86 transferable” machine guns are rare and expensive: $30,000 to $50,000+ for a transferable M16, and similar or higher prices for other popular models like the MP5, Thompson, and Uzi. A transferable M2 .50 cal can run well over $100,000.

Machine guns manufactured after 1986 are completely banned from civilian ownership under the Hughes Amendment to the Firearm Owners Protection Act. This fixed the supply permanently, which is why prices only go up. A transferable machine gun is one of the few firearms that appreciates in value like an investment, though that’s a heck of an expensive way to store your money.

There are some workarounds. Federal Firearms Licensees with a Special Occupational Tax (SOT) can manufacture and possess post-1986 machine guns for law enforcement and military sales. Some states allow machine gun trusts. And there’s a thriving market for “pre-sample” and “post-sample” dealer guns, though those come with restrictions on transfer.

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 (Knob Creek was legendary before it ended). For the semi-automatic rifles that share 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.

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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

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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 today.

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. And the tactical problems it created over a century ago are still being solved with every new generation of military doctrine and technology.

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FAQ: Machine Guns in Combat

Frequently Asked Questions