The Origin Of M2 Browning .50 Caliber Machine Gun


Of all the weapons to come from the genius of John Moses Browning, the M2 Browning .50 Caliber Machine Gun may have been his crowning achievement. It certainly was one of his finest, and one of the last to ever be born at the desk of this giant innovator of American guns.

Hands down, the “Ma Deuce,” as it’s reverently called by all who’ve witnessed it’s gracefully destructive power, is the longest produced machine gun the world arms market has ever seen. Browning’s design was finished in 1918, entered service with the US Armed Forces in 1921, and the patent was filed in July 1923.

It’s still manufactured and in use by militaries around the world to this day.

This king of automatic weaponry has seen action in more than 24 official conflicts around the globe, so our guess is that you’ve probably heard about it.

What you might not know is how the .50 Cal HB came into existence.

This is the Origin Story of the M2 Browning .50 Caliber Machine Gun.

John Moses Browning held the specs that had just come in from General John Pershing’s office.

It was July 1917, the climax of the Great War. Machine gun and cannon fire were now common place, making Europe a bloodbath as tens of thousands of men on both sides were slaughtered in a single day.

Machine guns using .30 caliber ammunition, like Browning’s own M1917, were already being used to keep enemy infantry buried in the trenches.

Due to the power of these early machine guns, the war front in Europe had largely come to a stalemate.

With men pinned down in the trenches, the war shifted to a battle of mechanical engineering. Both sides needed to find a relatively safe way across the barbed wire, trenches, machine gun fire, cannons, and insidious poison gases that made up the horrifying milieu of WWI.

British engineers lead the way with Her Majesty’s Landship Tank Mark 1 or the “Big Willie” as early as 1916. Germany came up with such behemoths as the Ehrhardt E-V/4 “Panzerkraftwagen” and the Kampfwagen series. The Allies responded by improving on the British Mark series.

It wasn’t until the technology of these steel plated juggernauts began to take to the skies that General Pershing sent his order to John Browning.

Breakthrough all-metal aircraft designs like Germany’s Junker Cl.1 made the current .30–06 machine gun mounted on Allied fighter planes ineffective.

Pershing put in his order. He wanted a gun that could deliver a bullet of at least 0.50 inches at a muzzle velocity of 2,700 feet per second.

The now sixty-two year old gunmaker mulled over the possibilities for the new design. John Browning paced through the shop, muttering and making indecipherable gestures as if assembling an imaginary weapon out of thin air.

Along with his colleague Fred T. Moore, Browning began the designs based on his previous M1917 .30–06 model.

They started by expanding the rectangular receiver body to chamber the monstrously large .50 BMG (Browning Machine Gun) rounds that Winchester would provide. It would feed ammunition from the left side utilizing a metallic link belt.

Browning and Moore delivered their finished design by the end of 1917, and tests began in 1918, the same year the Great War ended. The gun entered service officially in 1921, giving it its first designation the M1921.

John Browning testing his prototype .50 caliber heavy machine gun, circa 1919. 

But the M1921 had severe limitations.

It fired at less than 500 rounds per minute and could only produce a velocity of 2,300 feet per second. It was heavy, hard to control, and couldn’t pierce armored vehicles.

Both Winchester and Browning made improvements which brought the velocity to a deadly 2,750 ft/s and brought the rate of fire closer to 600 rounds/min.

By far though, the greatest weakness was the water-cooled barrel design.

The water jacket surrounding the lightweight tapered barrel kept the metal from overheating, which could lead to barrel fractures and catastrophic consequences for the operator.

This limited the use of the M1921 due to the need for fresh water on the front.

The water in the jacket would have to be replenished from time to time as the water inside would evaporate over time.

Replenishing the water jacket could prove deadly under fire and required more personnel to maintain the weapon’s functionality.

Not to mention the weight of water added to the overall bulk of the M1921. It was an unwieldy 121 pounds.

John Browning died five years after his greatest contribution to the small arms industry entered the service in 1926. He would not be the one to solve the barrel overheating problem.

It wasn’t until the 1930’s that the M1921 had undergone enough improvements to earn the machine gun mark “Browning M2.”

However, the M2 still used the bulky water-cooling system, even though this one featured a more efficient water circulation system.

A few short years after the M2 water-cooled model was being mass-produced by Colt, an air-cooled was developed. While able to hurl the massive .50 caliber rounds, it could only handle 75 rounds at a time before the barrel would fracture from the heat.

Enter the Browning M2 .50 caliber HB (Heavy Barrel).

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The much stronger barrel assembly was modified to dissipate the heat more efficiently, allowing it to be fired for longer periods of time.

The M2HB scaled in at a relatively portable 84 pounds and could now reach muzzle velocities of 2,900 ft/s. It’s impressive range gave it a killing distance of 2,000 or even 2,200 yards with some luck.

For these reasons, and because the “Ma Deuce” could spit out 750–850 rounds per minute with little to no malfunctions, made the Browning M2HB is one of the most prolific modern weapons the world has ever beheld.

Order our IRAC 2016 catalogue, or get your replica Browning M2 .50 CAL HB here.