Ask Ian: Why No German WW2 50-Cal Machine Guns? (feat. Nick Moran)

From Nathaniel on Patreon:
“Why didn’t Germany or Axis powers have a machine gun similar to the American M2?”

Basically, because everyone faced the choice of a .50 caliber machine gun or 20mm (or larger) cannons for anti-aircraft use, and most people chose the cannons – including Germany. There were some .50 caliber machine guns adopted by Axis powers, most notably the Hotchkiss 1930, a magazine-fed 13.2mm gun that was used by both Italy and Japan (among others). However, the use of the .50 caliber M2 by the US was really a logistical holdover form the interwar period. The M2 remained in production because it was adopted by US Coastal Artillery as a water-cooled anti-aircraft gun, and commercial sales by Colt were slim but sufficient to keep the gun in development through the 20s and 30s. It was used as a main armament in early American armor, but obsolete in this role when the war broke out.

However, with the gun in production and no obvious domestic 20mm design, the US chose to simply make an astounding number of M2s and just dump them everywhere, from Jeeps to trucks to halftracks to tanks to self-propelled guns. And that’s not considering the 75% of production that went to coaxial and aircraft versions…

Anyway, back to the question. The German choice for antiaircraft use was the 20mm and 37mm Flak systems, and not a ,50 MG on every tank turret. And so, there was really no motive to develop such a gun. The Soviets did choose to go the US route, though, and developed the DShK-38 for the same role as the US M2 – although it was made in only a tiny fraction of the quantity of the M2.

Thanks to Nick Moran (the Chieftain) for his assistance on this video! You can see the video he references about tanks being attacked by aircraft here:

And his full channel is here:
https://www.youtube.com/c/TheChieftainsHatch

40 Comments

  1. The Germans did actually produce a 13 mm machine gun, the MG 131, albeit only for use in aircraft, I believe it was very well built and lightweight but that the Luftwaffe preferred 20 mm cannon after all.

  2. This Q&A made me wonder, did anyone experiment with increasing the rate of fire (especially on the water cooled) M-2? High rate of fire should be beneficial for ground mounted anti-aircraft.
    Great work, keep up the good work.

    • I don’t know if this counts, with regards to your question, but the modern FN Herstal M3M (a “product-improved” M2) runs at around 1.100 rounds/min. As far as I am aware, the M3M is used only in aircraft installations (e.g. helicopter door mounts and gun pods).

      • The M3 was developed in the 2nd WW as a .50 BMG w/ a higher rate of fire. I believe the 1st aircraft it was fitted to was the P-80 Shooting Star, the 1st US operational jet fighter.

        • There are several variants of FN Herstal M3.
          The M3P is used in gun pods.
          The M3M (GAU-21 for the US armed forces) is used on aerial mounts (door, window, ramp…) but also on vehicles and naval applications (pintles and remote weapon stations).

  3. The MG 151/20 2cm aircraft cannon began as a 15mm machine gun, hence its odd designation. MG= Maschinen Gewehr, “machine rifle” (machine gun); MK = Maschinen Kanone, “machine cannon”, automatic cannon firing explosive shells.

    The Luftwaffe was of the opinion that anything bigger and heavier than a rifle-caliber MG on a fighter should be firing explosive shells. The major exception to this was the Bf109F-2, which replaced the twin 7.9mm MGs in the engine cowl with two 13mm MGs. In the Bf109F-4 and later Bf109G series, these were replaced with a pair of 2cm cannon. The cannon-armed versions can easily be spotted in wartime photos by the twin “bulges” in the cowling upper sides just ahead of the cockpit, to make room for the cannon ammo drums.

    The .50 MG was pretty much purely, not just an Allied but an American obsession. The Commonwealth forces preferred 20mm cannon to .50 MGs for aircraft use, and only the United States generally put anything heavier than a rifle-caliber MG on top of a tank or other AFV for AA defense. The British rarely bothered even with rifle-caliber MGs.

    This had rather amusing (?) results in North Africa after Operation TORCH. The American habit of bolting a .50 on a ring mount on top of half-tracks, trucks and SP guns came as a rather nasty shock to Luftwaffe pilots used to having it all their own way when strafing truck convoys.

    A strafing attack on an American convoy invariably was met with a shitstorm of .50 MG fire from almost every vehicle. It quickly degenerated into a gunfight with the odds heavily favoring the defenders on the ground.

    Let’s not even talk about the results of a typical ambush of the type usually pulled on British truck convoys by the locals.

    Playing “Cowboys and Indians” with an American transport company was a losing proposition.

    cheers

    eon

    • The BF109G only had the central 20mm cannon, firing through the propeller hub (and the possibility to mount another pairs in wing gondolas). The bulges where to cover the breech and belts of the 13mm MG131.

      • Side question: Why a machine gun or cannon firing through the propeller hub? I can see the impression that this would be easier for the pilot to aim. But the mechanical complications of getting such to work seem not worth to bother while adding maintenance and reliability issues.

        • Infact the central weapon (not yet a 20mm cannon, since it had not yet been developed) of the early BF109 models (those that operated in Spain for example) had reliability issues. But they had been already ironed out with the BF109e
          The central gun (developed also by the French) had the advantage of being much more accurate than wing guns, and with the weight more centred, while not requiring synchronization with the propeller. Synchronising a 20mm gun is more difficult than a MG (even if possible, infact the Soviets synchronised the ShVAK).

          • “(…)Synchronising a 20mm gun is more difficult than a MG (even if possible, infact the Soviets synchronised the ShVAK).”
            Certain variants of Imperial Japanese Army TONY fighter do have synchronized 20mm cannon in fuselage https://airpages.ru/eng/jp/ki61.shtml
            Ki-61-I-Tei(…)installation of Japanese 20 mm Ho-5 cannon in the fuselage decking(…)

        • “(…)Why a(…)cannon firing through the propeller hub?(…)”
          For single-engine aeroplanes of that era often engine was big part of mass of whole aeroplane, strapping gun to engine rather than frame of aeroplanes means that influence of recoil is much milder for that latter.
          Nonetheless such solution as has limitations and for example mating Yak-9 with 45 mm automatic cannon given unsatisfactory results http://ram-home.com/ram-old/gun-ns-45.html

        • it’s a synchronizing problem. it’s nigh impossible to synchronize an open bolt firearm due to timing problems. it’s easier to time the fall of a hammer in a closed bolt weapon that the breach lock of an open one.

    • With all due respect sir, the BF 109 never mounted a cannon in the cowling — only a singular one firing through the engine crank shaft and the propeller hub, the “motorkanone”. The larger guns that required the bulges were indeed the 13mm machine guns.
      The 109 could mount extra cannons but that was in the wing gun pods. Those weren’t these self-contained tubular things we mount on helicopters and jets these days, but indeed modifications to the wing’s shape that gave them these distinct bulges — better than gun pods for aerodynamics, but alas the flight performance still suffered compared to factory configurations.
      As for cowling mounted autocannons it was really only the Russians that mounted them there on prop aircraft in WW2.

      • The wing bulges on later 109s were actually for the enlarged landing gear wheels, which came about because the design got heavier over time. The 109 is a good example of how sometimes continuous evolution of a design goes wrong, because there came a point when fitting a more powerful engine couldn’t compensate for the extra weight and altered aerodynamics of the airframe. The very last models had tidier aerodynamics and a monster engine, but among other problems the greater torque made them a handful to fly (and land).

        The fundamental problem was that the 109 was built around a weak engine, so it had to be small and lightweight, which worked brilliantly until it didn’t work. Whereas the 190, Spitfire, P-51 etc had more room for growth.

        The gun pods were self-contained bolt-on, bolt-off units although I don’t recall if they were field-removable or not.

        • I think the “bulges” were not wing bulges but cowling bulges. I believe early Bf-109s used two 8mm cowl machine guns and the central cannon. I think later Bf-109s had a bulge on each side of the rear of the cowling for 13mm machine guns, and retained the same central cannon firing through the spinner.

    • “(…)MG 151/20 2cm aircraft cannon began as a 15mm machine gun, hence its odd designation. MG= Maschinen Gewehr, “machine rifle” (machine gun); MK = Maschinen Kanone, “machine cannon”, automatic cannon firing explosive shells. (…)”
      Luftwaffe simply consider everything below 30 mm to be “machine gun”, other 20 mm were also seen as MG by them, like for example MG FF or MG 213 https://www.bevfitchett.us/machine-gun-v3/info-hts.html
      Nonetheless MG 151/20 itself is mutually exclusive, as 15 is supposed to mean 15 mm caliber (like in MG 81 and MG 131)

      • Ehrm no. There was first the MG151 in 15 millimetre caliber that later got a variant with a 20 mm bore using the same cartridge case with a wider mouth. Just changing the barrel. The 20*82 mm cartridge is really short and stubby, but it allowed more effective explosive and incendiary projectiles. Although there were a few german aces that preferred to use the MG151 in 15 mm for its higher velocity. If you use an .50 (12,7 mm) M2 or a 15 mm MG151 does not make that much of a difference. For less experienced pilots the bigger effect on target of the 20 mm projectiles was considered worth it because the average pilot hit less frequently of course than an ace pilot.

  4. It’s interesting that the surface US Navy very rapidly went to a mix of 20 & 40mm, leaving Ma Deuce to the aviation & ground pounding sides of the house.

    • The Regia Marina, that adopted the 13mm Breda M31 in 1931, already replaced it with the 20mm Breda 20/65, on all the units big enough to carry it, before the start of the war.
      It was clear that, due to the evolution of the aircrafts, the 13mm had become a “vengeance weapon”, not something capable to stop the attacking dive/torpedo bombers BEFORE the launch.

    • Range. The navy needed to engage Japanese aircraft sooner rather than later. Towards the end of the war they even wanted fewer 20mm and more 40 mm.

  5. For the air role, where about 75% of M2s went, it makes sense that the US stuck with their already well developed and in production 50 as it was adequate for countering German fighters. The Germans needed to do the same, but also had the challenge of countering Allied bombers, for which an explosive round is far far better. I think that drove much of the decisions and the ground forces in both countries got what was on hand and in production rather than yet another custom developed MG/autocannon.

  6. The British had the .50 Vickers and 15mm BESA. In army use both were used as light tank and armoured car main armament, with the BESA replacing the Vickers.

    The 15mm BESA was very similar in performance to the later Soviet 14.5mm guns, or roughly twice as powerful as the .50 Browning.

    In naval use, the British used the .50 Vickers extensively, with quad mounts being pretty common. These were replaced by 20mm as the war progressed.

    Vickers had a .50 aircraft gun, but it was not widely used in the RAF during the 1930s because their analysis suggested that there wasn’t any advantage to it. If a .303 gun wasn’t enough, then you were better off with a 20mm than a .50 because the 20mm gave you an explosive shell.

    The Italians adopted a version of the .50 Vickers cartridge in their own aircraft machine gun design. They also developed an explosive bullet for it. What their explosive bullet mainly proved however was what people had been saying all along – that you couldn’t get a useful explosive charge into a .50 bullet because the fuse took up too much space.

    As mentioned, the French developed a 13.2mm Hotchkiss gun which was very widely sold on the export market. Prior to WWII this gun was probably the most widely used heavy machine gun when measured in terms of number of countries adopting it.

    The Germans had 13mm and 15mm guns, but only in aircraft use.

    US aircraft used .50 because the US 20mm aircraft cannon project was a procurement and manufacturing fiasco. The US was the last major country to enter WWII. Had the US entered the war at the beginning or if the war had gone on longer the US might have had time to straighten out its design and manufacturing problems and use 20mm guns on its fighters more extensively.

  7. “Why didn’t Germany or Axis powers have a machine gun similar to the American M2?”
    If you use Axis as proposed by http://www.presidentlincoln.com/cleese,%20axis%20of%20evil.html then this limit them to III REICH, KINGDOM OF ITALY, EMPIRE OF JAPAN, with latter have counterweights as already explained, however another definition of Axis do include FINLAND, which used machine gun very like M2, namely LKk/42 see photos http://airwar.ru/weapon/guns/lkk42.html

  8. I would like to correct a mistake made by Ian in his video. None of the 20mm guns in WWII used proximity or timed fuses. These were all impact fused shells.

    To put things in perspective, consider a typical early to mid 1930s aircraft. These were metal or metal and wood structures covered with aluminum sheet or fabric, or a combination of both.

    In order to cause damage to one of these aircraft a bullet had to hit something vital. Without a direct hit on something vital a bullet would just pass through making a small hole that was easily repaired.

    In order to have a reasonable chance of causing significant damage this required a lot of bullets to be fired, which in turn required lots of fast firing machine guns. Air to air engagement distances were fairly short, so having enough range wasn’t an issue.

    Using heavier calibre machine guns meant carrying fewer and slower firing guns, while the larger bullet would in most cases not cause significantly greater damage.

    A 20mm gun however was a game changer because it could fire a useful explosive shell. Even a single hit from a 20mm shell had a reasonable chance of causing significant damage from the many fragments produced by the shell. Producing the same effects from a non-explosive machine gun would require many direct hits.

    As aircraft got heavier and stronger advantages did develop for .50 guns over .303 (or .30), but 20mm was still better again than .50.

    In bomber turrets with multiple guns however machine guns retained an advantage over 20mm guns because the vibration of the heavier recoil of the latter caused too much dispersion of the shots. Doing something about this would require synchronizing the firing of all the guns in the turret, and doing that would require a completely new gun design. That wasn’t something that was going to happen in the time available in the war.

    The US had multiple .60, .90, and 20mm projects operating in parallel during WWII trying to develop an aircraft gun to replace the .50. None of them were successful. That requires a long explanation of its own, but it’s not as if the US weren’t at least *trying* to develop a 20mm aircraft gun.

  9. One might think the Germans were short sighted with having no 12.7mm machine guns mounted on their tanks for AA and infantry support. The simple answer was: They were. Countries make mistakes. The problem is that decisions for equipment are often years behind implementation, often the right choice is just a matter of designed something years before and and having the production facilities just around when the weapon became useful for something it hadn’t necessarily intended. The US Army was in a constant tug of war regarding the best armored equipment from the 30’s through the war. The USN made a gigantic mistake with torpedoes and the US paid the price in 1941-1943. It is so much easier to solbe problems with hindsight than with foresight.

  10. Yet again we see the disconnect people have when it comes to weapons and weapons design.

    Look, if the Germans had felt like a .50 M2HB was desirable and worth having, they’d have had it. Instead, they felt that a high rate of fire in a rifle-caliber MG and some light autocannon were preferable tools for the roles that the US put the M2HB into. This is where the flaw in the thinking lies, with the very basis of this question–It’s not that the Germans didn’t have the ability to produce something like the M2HB, it is that they didn’t think it was a good fit for their needs. Why add a third caliber, down in the infantry and tank platoons?

    As well, the Germans were working in a much different AA environment than the Allies were: Try shooting a Sturmhovik down with anything smaller than a 20mm. You won’t find it fun… A non-explosive round that was nearly as logistically costly, like the .50 Browning, wasn’t in the cards. Too small, no explosives.

    The whole question boils down to doctrine, and the proper way to phrase this isn’t “Why didn’t the Germans have an M2HB equivalent?” but “Why did the Germans feel they didn’t need one?”, and that question is answered by “not in their doctrine”.

    The prevalence of the .50 in the US military stems from one thing, and one thing only: We could afford the things, and they were a handy tool to have around. As well, the US basically used the M2HB for things that other armies issued anti-tank rifles for; where they intended to fire one round at a time through things like the Boys AT Rifle, the US was kinda like “Well, if one round is good, how about twenty or thirty…?” During the early days, the M2HB was kinda the TOW missile equivalent, or like the old ADATS system in intent–Multi-purpose air defense/AT work. It aged out of the role as armor got heavier on tanks and aircraft.

    In short, the question isn’t necessarily wrong, it is that it is misconceived. The Germans didn’t have an M2HB equivalent because they didn’t feel like the weapon was necessary or useful, in their doctrine. They felt that an effective air defense at that level was better served by 20mm fire with explosive rounds, period.

    • Kirk, you are dead on. The Germans designed the machineguns they did ACCORDING TO their needs. As well as their machinegun doctrine.

    • Wasn’t the MG 42 also given a flak mount and ring sights just in case of low-flying attacking aircraft? Sure, a rifle bullet won’t do much damage, but several hundred delivered to the belly of a plane tend to reduce the attacker’s crew to honeycomb. Just imagine the end result of a squadron of Hawker Hectors strafing machine gun trucks… I could be wrong.

      • Infact is again a question of perceived effectiveness. You can see that, also on defensive installations on aircrafts, the Germans preferred to use twin 8mm MG81 instead of single 13mm MG-131. On the contrary the Italians preferred the single 12.7mm Breda SAFAT, using the 7.5m one only when space or wheight constraints left no alternatives.

  11. AFAIK, the only antiaircraft shell to have a proximity fuse in WW2 was the 5 inch shell. Ian seems to indicate that there was a 20mm proximity fuse, which believe is not the case. I believe that while a 20mm exploding shell had more explosive than a 50 cal, it still had to hit the aircraft or other target to detonate. And, I believe that there was a 50 cal exploding round (blue tip) in addition to the silver top Armor Piercing Incendiary which had only a incendiary flash, which can be often seen in gun camera footage as ~12 inch diameter white flashes on trains or aircraft. Whether the blue tip was available in WW2 or a postwar development, and whether it was used in WW2, I don’t know, but I believe that such a cartridge/bullet existed or may even still exist.

    As a side note, the 5 inch anti-aircraft proximity fuse, which used a miniature radar unit, which was extremely advanced for the era, was prohibited over Europe so that unexploded shells couldn’t be recovered and reverse engineered by the Germans. They were only used over the Pacific where essentially all of the unexploded shells would fall into the ocean.

  12. As for the Anti Aircraft use, the USA was hardly limited to the .50

    We had the 37mm Browning in the M1 (on Carriage M3A1) used by CA units and the USMC , the 40mm in the Bofors M1, used by USN, USA, USMC

Leave a Reply to Dogwalker Cancel reply

Your email address will not be published.


*