First to the Fight: The Marines’ Reising M50 SMG

Eugene Reising developed a .45 ACP submachine gun in the late 1930s that was basically the opposite of the Thompson – it was light and handy, fired from a closed bolt with a delayed blowback action, and was inexpensive to produce. Reising contracted with Harrington & Richardson to produce the gun, and when it entered the market in early 1940 it found immediate interest form the USMC. Looking initially to equip the Marine Paratroop Regiment (Paramarines), the Corps wanted a gun that was light and compact. The Reising M55 with it folding stock was certainly those things and since the Thompson was essentially unavailable anyway (all production was going to the Army and foreign contracts), the Corp adopted the Reising with initial purchases of both the M50 and M55 in January and February of 1942.

What we are looking at today is an early production M50. It is blued with 29 barrel fins and the early style of sights, stock screw, trigger guard, magazine release, stock (the lacquer coating and sling swivels having been added by a previous owner), and firing pin. Later production guns would be improved and strengthened in various ways, but the Reising would never quite meet the needs of frontline combat troops, much to the displeasure of the Marines who first used them in the Pacific theater. Lacking interchangeable parts and susceptible to fouling and malfunctions, the Reisings were quickly replaced by other arms – some Johnson M1941 rifles, some M1 and M1A1 carbines, and various other guns. Rotated back to duties like ship boarding parties, guards, and military police, the Reising served very well. They were indeed handy and accurate guns, jut not built for the extreme rigors of Pacific beach assaults and jungle foxholes.


  1. For a time during WWII, my dad was a USMC guard at the naval prison. He was issued a Model 50, but never fired it. We used to have a photo of an assembly of the guards there, with all having one.

  2. IIRC many of these were sent out via lend lease – I’ve seen pictures of Russians with them…
    The example you are reviewing – re: Sling loop location. I have an example here (FA) with an unvarnished stock and sling loops on the bottom edge of the stock with a serial just a bit over 1000 higher… So this one missed the sling installation by just a little bit it would seem…

  3. God, Ian, NEVER call a jump qualified Jarhead a “Paramarine”! GEN Holcomb, the Commandant 1936-43, would go into a spittin’ rage when he heard someone use that term, saying that it was calling these men “almost marines” (“Par-cooking is a process by which food is partially cooked so that it can be finished or reheated later” “from Greek para ‘beside’; in combinations often meaning ‘amiss, irregular’ and denoting alteration or modification.”). It’s rather like the term paramilitary – meaning militia, irregulars or not officially recognized armed bands.

    • As I am sure you realize, you are mixing roots and modifiers. The “par” in “par-cook” means “part” (partially cooked). The “para” in “paramilitary” means alongside (as in parallel). The “para” in “parachute” means “against” (“against falling”). The “para” in “paramarine” means “somebody shut this guy up, already!”

  4. “displeasure of the Marines” The story that I heard was that the CG of the 1st Marine Division (you have to specify – The First Marines is a regiment) ordered that all the Reisings be turned in and then had them loaded onto a landing craft, taken out into Iron Bottom Sound and deep sixed. He then told his G4 to report them as “lost in combat”, I can see why he became Commandant.

    War story time (What’s the difference between a fairy tale and a war story? One begins “once upon a time” and the other begins “three I was”). In the seventies, my dad’s ship – an aircraft carrier – began having annual reunions. One time it was near where I was stationed and I took some leave and joined him and mom. One evening, being a ground pounder (Army not Gyrene), I gravitated to where the ship’s marine detachment (In WW2, all battleships, fleet and light carriers and cruisers had one) was having its own private gathering. Naturally, there considerable curiosity on their part about our modern weapons and I asked them what they thought about their weapons. They had been equipped with M1917 pistols, M1903A3 rifles, Reisings (solid stock version), trench guns (unknown model) and M1918A2 BAR’s. They liked the M1917’s, thought the A3 was a step down from the original (which in fact, it probably was, in terms of quality. But as old soldier who owns A3 I think as a combat rifle, it was just fine). The Reising – “nobody trusted it”. What about the BARs? The guy whod been their CO spoke up. “I gave them away”. As a serving officer, I was stunned – that sort of thing meant court martial! He said, he ran into a friend who had been in his platoon in OCS at an O Club ashore who was now commanding an infantry company. His friend mentioned he wished his outfit had more BAR’s. The ship’ detachment CO had a brilliant idea – one worthy of Baldrick -“Come out to my ship tomorrow at 1000 hours and I’ll help you out”. His friend did and he took him down to the armory, told the armorer to make up a hand receipt for their four BAR’s and gave them to his buddy. Both the armorer and his First Sergeant had protested, but he had waved them aside. “The guns were still under control of the Corps. What was I gonna do with them? Use them to repel borders? And what could they do to me, draft me and send me to combat?” (the detachment manned some of the AA guns when at General Quarters)

    • And a sea story begins with (look around to make sure nobody’s listening, lean forward, and speak quietly) “Now this is no shit …”

      • I had always heard that they were thrown into the Tenaru River on Guadalcanal. I possibly got the story from “Rifles and Machine Guns”, by Melvin Johnson. My dad bought a copy during WWII, so he could see and understand a lot of the weapons he would see. I still have the book, but it’s deep in a closet.

  5. I feel sorry for the Reising, a baptism of fire on Guadalcanal was the hardest test any gun could face, and meant it has been looked on a junk, which is unfair.

    The test firing should be good.

  6. Such a shame they lavished so much funding on upgrading the Thompson, when it would have been better spent on simplifying the inherently superior Reising.

    • claims that Reising sub-machine gun was examined in Soviet Union, although apparently not subjected to full roster of trials, conclusions:
      – delayed blow-back make whole system more complicated, but allowed lowering mass of moving parts by 0,2…0,3 kg and whole weapon, first lessen vibration during firing full auto
      – “Reizing” is substantially complicated in stripping, and especially production in production, due to requiring exact preparation of details and does not allow stamping in preparation of separate details
      – construction of magazine does make it hard to refill it, moreover dirt or dust cause excessive friction, which might lead to lack of cartridge feed
      Interestingly Rate-of-Fire measured was found to be 775 rpm, which is definitely another value than claimed by manufacturer 500…550 rpm

      Thus I presume “(…)simplifying the inherently superior Reising(…)” would not help as magazine was causing malfunctions.

      • The Thompson magazine is definitely better, but adapting it to the Reising would be a fairly simple matter (feedramp and possibly a wider bolt feed tab). The only reason the Thompson mag has the weird lockup “T” on the back is because it was originally designed for wells designed to also hold drums. An adaptation could simply treat is as a deeper magazine (especially since the Reising mag already has a protrusion on the back, and uses a similar catch).

    • If I understand correctly, the Reising was never really on US Army’s radar, and the poor experiences of the Marines made it certain that it never raised any interest in the Army. The design had multiple problems from a military point of view and it wasn’t at all sure that all of them could have been fixed adequately. For example the disassembly was quite complex and simplifying it significantly would have probably required a fairly major redesign. Ian’s earlier video about to M55 shows it nicely:

      • I know and love the earlier video; it’s where I came to this conclusion (and figured out how I’d do it using simple methods readily available in the 40s).

        Disassembly: Lock rear tab of magwell into a notch in receiver and retain the front using the tail of a captive recoil spring.

        There’s more, but the above steps would address all the Marines’ issues with the original.

  7. Post-war the US Border Patrol ended up with a bunch of them.

    There is a photo of a Navajo code talker with one next to his radio.

  8. I have a model 50 and it’s a fantastic SMG. Good ergonomics and easy to use but I’m not belly flopping on any beaches or trenches in the rain. Very fast rate of fire but can be difficult to control in full auto due to light weight. Was told or read somewhere that Marines would take off rear of sling and stand on it to control full auto. Tried that and it actually works pretty well. Also very controllable firing in short bursts. Great video! Cant wait to hear what you think after you use it on the range.

    • Seems like a dangling sling would interfere with marching. Detaching a sling end takes a second or two. Bad idea in a fight, wasting time. Also standing up in a fight is often unwise unless one id shooting around cover

  9. Such a near miss. Interchangeable parts, adequate finish, adequate magazines…
    Perhaps as semi-auto only, it might have taken the place of the M1 carbine.
    How did the 1928-style Thompsons do in the jungles?

    • My boss, Marine Guadalcanal, was issued a Reising before landing. He stated that if you could keep it clean it worked perfectly. The trouble was that Guadalcanal was anything but “clean”.

      When the Army arrived on Guadalcanal in support (164th, 123rd and 134th Infantry, forming what was then named the “Americal” division, from “AMERIca” and “New CALedonia”), they brought TSMGs with them, primarily M1921s and M1928s as the M1 and M1A1 were not yet in full production.

      When the order came down to turn in the Reisings, my boss, being a sergeant, was allowed to draw an M1921 Thompson from the Army stores. He kept it until Okinawa. There, he fell foul of a land mine and ended up being sent to the rear for medical care. The M1921 stayed with his unit.

      He was in the base hospital at Pearl Harbor recovering from surgery on his right leg, and was told he’d be fit for duty in time for the invasion of Japan proper, during the first week of August 1945. Needless to say, that invasion turned out to be rather different than expected after the events of the 6th and the 9th.



  10. My memory is fuzzy on this, but I recall a number of demilled Reisings ended up as arcade game props in the 60s and 70s.

  11. I think you got the function wrong:
    The friction of the bolt in the recess alone would’nt make any more difference than the “Blish Lock” of the Thomson.
    But in order to drop, the bolt must accelerate the action-bar over the ramp at probably many times the rate it is itself moving backward.
    Because of that, from the point of view of the cartridge and for the first mm or so of bolt travel, it is the same as if the moving parts were heavyer than they actualy are,
    like in a MP5.
    BTW I Love your content, Ian.

  12. A simple way to test my theory:
    Push on the bolt thru the barell with a threaded rod, with a nut and counter-nut on it adjusted to push exactly one milimeter.
    If I’m right, the action Bar should move at least 1.5 mm.

    If I’m wrong, why is the contact surface between bolt and action bar slanted?
    A lock based on friction can not work reliably, because the friction varies to much between “clean and lubricated” and “dry and dirty”.

    Pardon me for insisting, but I can not stand to see “gun Jesus” go wrong.

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