Imagine for a moment, World War Three finally erupts. The draft is issued, and governments the world over scramble to conscript their citizens in preparation for the ultimate battle of East vs West. You’re anxious about facing the enemy, but take comfort in knowing that you, a soldier of the free, democratic world, hold the technological scale tipped firmly in your favour, giving you the definitive edge against your opponent.
Now how would you react upon discovering that among your super modern, high-tech arsenal, you may be sent into combat fielding World War One era weaponry? – Probably something along the lines of ‘WTF?’.
While you may be conjuring images of bulky bolt-action rifles and horse drawn artillery pieces, there are but a couple of notable exceptions that would seem at home amid the carnage of the modern battlefield, and there are none more notable than that of the 50 Calibre M2 Browning Machine Gun, or the Ma Deuce as it’s colloquially dubbed; the longest produced machine gun the worlds arms market has ever seen.
This behemoth of a machine gun has faithfully and dependably served several generations of soldiers since the outbreak of the Second World War, and has since appeared in every major armed conflict around the world in a variety of models and configurations.
From the dense urban cities of Western Europe to the humid jungles of Vietnam, the frozen steps of the 38th Parallel and the arid, dust strewn sandscapes of 21st century Afghanistan and everything in-between, the Browning 50 Cal has cemented itself as the poster child of post 20th century warfare.
Having been adopted as the primary heavy machine gun of all NATO member countries and various other worldwide nations, the M2 is about as unavoidable in the modern theatre of war as American intervention in a politically turbulent, oil rich country.
This Swiss army knife of the machine gun world is utilised in a smorgasbord of offensive and defensive roles, including, but not limited to: anti-aircraft, anti-armour, anti-personnel, and generally anti-anything you decide to aim at and press the trigger. In this episode, we’ll be taking a look at why the Browning M2 has stood the test of time and examining what makes this heavy machine gun the quintessential armament of the 21st century.
Chapter I: Development History
As World War One unfolded, weapons of larger than rifle calibre were steadily introduced to both sides of the conflict. The larger rounds were a much-needed answer to the increasingly durable armour seen both in the sky and on the ground. In August 1917, Imperial Germany deployed an all-new, cutting-edge armoured aircraft to serve in low-level ground attack and reconnaissance roles on the Western Front.
The Junkers J.I. – or ‘steel bathtub’ as it’s affectionately known, was an armoured J-Class sesquiplane that featured a single unit of steel armour plating that ran from behind the propeller to the rear crew position, encasing its crew, engine, fuel tanks and radio equipment in a formidable 5 millimetres (0.20 Inches) of protective steel armour plating, weighing in at a hefty 470 kilograms (1,040 lbs).
This thicker armour plating rendered attempts to shoot down the aircraft with conventional rifle calibre ammunition – such as the American .30-06 cartridge – ineffective. At this time, US Colonel John Henry Parker was commanding a machine gun school in France and observed the effectiveness of a French 11mm armour-piercing incendiary round, believing that a similarly capable cartridge would be instrumental to the American war effort.
The increasing demand for firepower was overwhelming, and in April 1918, General John Joseph Pershing (or Blackjack Pershing) – Commander of the American Expeditionary Force – contacted the United States Army Ordnance Department and formally requested a larger calibre machine gun that fired a projectile of .0.50 Inches with a muzzle velocity in excess of 2,700ft/s.
This substantial increase in firepower was originally intended to serve in both an anti-aircraft and anti-armour role. There was just one problem. Neither a cartridge of this size nor the gun to fire it had yet to be invented.
The United States Army Ordnance Department contacted the renowned gunsmith and engineer John Moses Browning who immediately set about designing the new armaments. Luckily for Browning, the Germans had already begun experimenting with unusually large calibre ammunition for use in anti-tank warfare.
The Mauser Tankgewehr M1918 or TuF, short for Tank und Flieger, or “tank and aircraft” was an absolute beast of a rifle, chambered in the newly developed 13.2x93mm SR cartridge, it was essentially a scaled-up version of the Mauser Gewehr 98 – the standard German infantry rifle of the era – and packed one hell of a punch.
This tank killer was a single-shot weapon that had to be manually reloaded after each shot. It differed from other rifles of the era in that it featured a pistol grip, bipod, and a barrel almost 1-metre in length. The new cartridge featured a muzzle velocity of 2,700ft/s and an 800-gram projectile that could penetrate 1-inch of steel armour at a range of 230-metres (251 yd).
Such a rifle was developed after the British had launched a large-scale tank offensive at Cambrai in the fall of November 1917, the largest deployment of armour during the war that saw 476 of the new British Mark I tanks push German forces back some 20 kilometres (12 miles).
A number of these rifles were captured by advancing allied forces and were shipped to America where they could be properly analysed and assist in the development of Browning’s latest assignment.
Already credited for such iconic small arms designs as the M1911 semi-automatic pistol, the Browning Automatic Rifle (BAR) and the M1917 water-cooled machine gun, Browning set about scaling up the M1917 for a heavier cartridge of his own design. Working alongside The Winchester Repeating Arms Company, Colt, and later Frankford Arsenal, Browning scaled up the .30-06 round to .50 calibre (12.7-millimeter) and adopted it for the resulting new machine gun, the water-cooled M1921.
The M1921 weighed 35 Kilograms (79 lbs) without water and boasted a firing rate of 500 rounds per minute.
Unluckily for Browning, or, perhaps luckily for your average German infantryman, the prototypes were ironically ready for testing just in time for the war to end on 11th November 1918. While the US army saw obvious potential in the joint Colt-Browning design, the enormous power of the 50 BMG – or 50 Browning Machine Gun – cartridge proved far too excessive for their initial model and forced both companies back to the drawing board.
During the interwar years, Springfield Armoury aided Colt in further development of the M1921 by contributing swaths of resources and engineers. Among those dispatched to Colt was Springfield engineer Doctor Samuel Green who built upon the established design and made some significant improvements.
The addition of a cammed charging handle allowed for easier charging of the weapon, alteration of the belt holding pawls facilitated the ambidextrous feeding of ammunition, a universal receiver and front trunnion that allow for internal and external component interchangeability, and perhaps most notably of all, the addition of a heavier, air-cooled barrel that relinquished the need for water-jacket cooling.
These vast design improvements ultimately culminated in the iconic Browning design seen worldwide today. Official designation: Browning machine gun, cal. .50, M2, HB (Heavy Barrel).
Chapter II: Features
Depending on the model, the M2 features varying cyclic rates of fire. For instance, the M2HB air-cooled ground gun has a cyclical rate of 450–575 rpm, while Aircraft configurations such as the AN/M2 and AN/M3 feature a cyclic rate of 750–850 rpm and 1,200 rpm respectively. These maximum cyclic rates are mainly hypothetical, as sustained fire at such a rate risks wearing out the bore of the barrel within a few thousand rounds and will require a replacement.
If going all Rambo isn’t quite your style, the M2HB can be selected to fire semi-automatic single shots at less than 40 rpm. Slow and rapid firing modes use 5–7 round bursts with different pause durations between bursts.
If the bolt release is locked in place by the bolt latch release lock on the buffer tube sleeve, the M2 will function in fully automatic mode. Alternatively, unlocking the bolt release into the up position will enable single-shot semi-automatic firing upon pressing the bolt latch release to send the bolt forward.
The closed bolt firing cycle made the M2 usable as a synchronised machine gun on aircraft before and during World War II, as on the early versions of the Curtiss P-40 fighter.
Throughout World War II, the warplanes of the US Army Air Force were almost universally equipped with the Browning 50 Cal. Fighter planes used the M2 in the offensive role, while attack aircraft and bombers used them defensively to ward off intercepting enemy fighters.
The P-51 Mustang had two banks of three M2 machine guns in each wing, with the six machine guns providing the legendary fighter aircraft with a powerful punch against both ground and air targets. The P-47 Thunderbolt and P-38 Lightning were also equipped with the M2, as were the B-25, B-26, B-17, and B-29 bombers.
The M2 boasts an effective range of 1,830 metres (2,000 yd) and a maximum effective range of 2,000 metres (2,200 yd) when fired from the M3 tripod. In its ground-portable, crew-operated configuration as the M2HB, the gun itself weighs 38 kilograms (84 pounds) and the assembled M3 tripod adds an additional 20 kilograms (44 pounds) to the overall weight.
In this configuration, the V-shaped ‘butterfly’ trigger is located at the very rear of the weapon with a ‘spade handle’ grip on either side, the bolt release is located in the centre and standard configurations feature a rear type leaf sight.
The spade handles are gripped, and the butterfly trigger is depressed with one or both thumbs, discharging the weapon. Recent modifications to the rear buffer assemblies have seen squeeze triggers mounted to the hand grips, foregoing the traditional butterfly triggers.
In stark opposition to virtually all other modern machine guns, the M2 doesn’t feature a conventional safety mechanism. Instead, some soldiers resort to improvised measures to prevent accidental discharge. One such method is to insert an expended shell casing behind the butterfly trigger to prevent depression.
As the M2 was designed to operate in multiple configurations, it can be adapted to feed from either the left or right side of the weapon by exchanging the belt-holding pawls and the front and rear cartridge stops, then reversing the bolt switch.
The operator must also convert the top-cover belt feed slide assembly from left to right hand feed, as well as the spring and plunger located in the feed arm. Despite its rather convoluted sounding nature, this process should take a competent and well drilled soldier no-less than two minutes to achieve.
The charging assembly can be switched from left to right hand charge. A right-hand charging handle spring, lock wire, and the necessary training is all that’s required. The M2 can be battle-ready and easily interchanged if it is pre-emptively fitted with a retracting slide assembly on both sides of the weapon system, negating the need to withdraw the weapon from service.
The 50 Calibre cartridge consists of a cartridge case, primer, propelling charge, and the bullet. The term bullet refers only to the small-arms projectile that’s propelled from out of the barrel. There are eight types of ammunition issued for use in the 50 Calibre machine gun, with the tips of the various rounds colour-coded to indicate their type.
These include: standard ball, tracer, armour-piercing, incendiary, armour-piercing incendiary, armour-piercing incendiary tracer, dummy rounds and blanks. Ammunition boxes typically feature a 100 to 200 round capacity.
Chapter III: Variants
The rudimentary M2 design was adopted by the US military in 1933 and has since showcased in a number of sub-variants, each featuring unique designations as per the US Army system. For instance, the development of the M1921 which ultimately paved the way for the M2 was water-cooled and featured a flexible mount, and was thus designated ‘Browning Machine Gun, Cal. .50, M2, Water-Cooled, Flexible.’
Think of the varying designations as a system of identification for the model in question.
Improved air-cooled heavy barrel variants came in three subtypes: The basic infantry model, ‘Browning Machine Gun, Cal. .50, M2, HB, Flexible’, a fixed mount version that was developed for use on the M6 Heavy Tank, designated ‘Browning Machine Gun, Cal. .50, M2, HB, Fixed’, and a turret type, whereby “Flexible” M2s were modified slightly for use in tank turrets.
The subvariant designation Browning Machine Gun, Cal. .50, M2, HB, TT was only used for production, supply, and administration and identification purposes.
A variety of additional sub-variants were developed by the United States following the conclusion of the Second World War. The Calibre .50 Machine Gun, Browning, M2, HB, M48 Turret Type was developed for the commander’s cupola on the M48 Patton tank.
The cupola mount on the M48A2 and M48A3 tanks were generally disliked by most tankers, as it proved unreliable in service. An externally mounted M2 was later adopted for the commander’s position on the M1 Abrams tanks, which you’re likely familiar with if you’ve ever seen newsreel footage of US military operations in the Middle East.
Three sub-variants were also developed for use by the US Navy on a variety of ships and naval vessels. These included the ‘Calibre .50 Machine Gun, Browning, M2, Heavy Barrel, Soft Mount’ and the ‘Calibre .50 Machine Gun, Browning, M2, Heavy Barrel, Fixed Type’. The fixed variants fire from a solenoid trigger and come in left- or right-hand feed variants for use on the Mk 56 Mod 0 dual mount, and various other mounts typically utilised in anti-aircraft roles.
The M2 E-50 is a long overdue upgrade programme for existing infantry M2HBs and other M2s currently in U.S. military service, featuring the new: Quick Change Barrel (QCB) capability, an improved flash hider, a rail accessory mount, fixed headspace and timing, and a manual safety feature.
The designation ‘E-50’ is a term that refers to a developmental project that stands for ‘Enhanced 50’, as in enhanced .50 Calibre machine gun. It was developed primarily as a conversion kit for existing units, though it’s likely that newly produced M2s will be built in accordance with these updated features. These variants are sometimes referenced as the M2E2 or M2A1 in U.S. Army briefings.
Chapter IIII: Accolades
When partnering the M2’s semi-automatic capability with the immense fire power of the 50 BMG cartridge, the addition of the M3 tripod and a mounted high-power scope, the M2 adopts the role of a deadly efficient long range sniping weapon that can be used to devastating effect.
In the case of the now infamous U.S. Marine Corps sniper, Gunnery Sgt. Carlos Hathcock, this is exactly what occurred when in 1967 during the Vietnam War, he managed to neutralise an enemy target from a staggering 2.28 kilometres away, that’s 2500 yards, or just under one and a half miles, achieving the longest distance kill in history up to that point.
In the 1998 book Inside the Crosshairs: Snipers in Vietnam, retired U.S. Army Lieutenant Colonel Michael Lee Lanning and author described the shot as such:
“Firing from a hillside position using an Unertl 8X scope on a .50-calibre machine gun stabilised by a sandbag-supported M3 tripod, Hathcock engaged a Vietcong pushing a weapon-laden bicycle at 2,500 yards. Hathcock’s first round disabled the bicycle, the second struck the enemy soldier in the chest.”
The uncanny ability of the Ma Deuce to make heroes of some men and mincemeat of others is one that has been well observed and documented since the onslaught of the Second World War.
In one such case, decorated soldier and medal of honour recipient 2nd Lieutenant Audie L. Murphy distinguished himself as a symbol of American fighting ferocity and resilience in the face of overwhelming odds, when on January 26th, 1945, he was commanding company B of the 15th Infantry Regiment, 3rd Infantry Division, near the French village of Holtzwihr when six German tanks and several hundred infantrymen attacked his company.
Murphy ordered his men to fall back to defensive positions in the nearby woods while he covered their withdrawal and called down artillery to slow the German advance. German fire hit an American tank destroyer nearby and set it on fire. Witnesses later recalled:
“He climbed on the burning tank destroyer, which was in danger of blowing up at any moment, and employed its .50 calibre machine gun against the enemy.”
From Murphy’s exposed position on top of the burning tank destroyer, he killed over 20 German soldiers and repelled their attack for over an hour using the M2 machine gun, despite suffering wounds to his leg. He then led his company in a counterattack that killed or wounded 50 more German soldiers.
In what must be the ultimate testament to the longevity of John Moses Browning’s engineering ability, a seemingly ordinary M2 .50 Calibre machine gun was recalled from active duty to the Anniston Army Depot in Alabama for compulsory maintenance and an upgrade to the M2A1 configuration.
At first glance, this particular model didn’t seem any more notable than any of the other thousands of units that pass through each year. But upon closer inspection, this particular gun was seen to bear the serial number 324, indicating that this model was one of the original 1933 Colt run productions, having served for upwards of 89 years.
It’s difficult to imagine what the face of warfare will look like a hundred years from now, whether the battles of tomorrow will be fought with robots, advanced alien technology, or even on another planet altogether. But whatever the future may hold, it’s safe to say, there’s a likely possibility that the Ma Deuce, in one form or another, will retain its place on the modern battlefield, just as it has for the previous 100 years.