James D. Julia: Johnson LMG History & Disassembly

The Johnson light machine gun is one of the lesser-known US military machine guns of WWII, although it seems to have been very popular with all those who used it in combat. Melvin Johnson made a commendable attempt to get his rifles adopted by the US military, but was unable to unseat the M1 Garand as American service rifle. However, he did make a significant sale of both rifles and light machine guns to the Dutch colonial army.

By the time those Dutch guns were ready to ship, however, the Japanese had overrun most of the Dutch islands. The guns were thus basically sitting on the docks with nowhere to go, and at that point the US Marine Corps took possession of them. Because of their short recoil action and quickly removable barrels, the Johnson guns were ideal for airborne Paramarines, and saw use in the Pacific with these forces. They were also used by the joint US/Canadian First Special Service Force in Italy.

In many ways, the Johnson LMG is similar to the German FG-42, although with more emphasis on full-auto use instead of shoulder rifle use. It fired from a closed bolt in semiauto and from an open bolt in full auto, and had a bipod both effective, light, and easily detachable. Overall the Johnson is a light, handy, and very easily dismantled weapon, and its popularity with combat troops seems well deserved.


  1. A very neat weapon, thanks for sharing it with us.
    Some comments:
    1 – No means to handle a hot barrel during changing, seems to be an American thing, the M60 had the same failing.
    2 – Very neat feed system with replenishment by stripper clips, must have come in useful to keep the magazine topped up except that it had to be done on the right hand side, where it’s also ejecting empty cases.
    3 – Really fiddly business getting the bolt handle off, you would never do it in North European winter conditions, a more mature approach would be a smooth knob with a hole for a bullet point. In any case the handle and the extractor are asking to get lost during field stripping.
    4 – Very advanced firing mechanism, way ahead.
    5 – The magazine on the side is neater than above and much more convenient than below, but doesn’t it tend to make the weapon pull to the right on full auto? I remember the Sterling SMG did that on a full mag. Perhaps it’s just a question of habit, aim off to the left and let the gun cover the target with a short burst. After all you are supposed to spread it about a bit.
    6 – Rear sights look a bit fragile, and the front sight could do with protection. It does not seem to be zero-able, is that so?
    In all a very nice gun, the “Mk II” would address any issues raised by field use and it would mature very nicely.

    • “In all a very nice gun, the “Mk II” would address any issues raised by field use and it would mature very nicely.”
      Johnson created Auto-Carbine (as he called it) which is at one time derived from Johnson LMG and from Johnson rifle, see 3rd photo from top here:
      Objective was to get lighter and shorter guns because of the short stature of its native troops

    • If I’m not mistaken the clips were never shoved into the ejection port. There was a separate opening with a clip guide above the port, right?

      In any case, the Johnson was still way ahead of its time save for having no way to man handle a hot barrel, just as you said. A carrying handle would have been a good addition.

      • Correction on the previous comment: Clip guide is below the ejection port. No sane man would try to use the loading gate while the gunner is actively suppressing the other team! As for issues with weapon balancing on fully automatic shooting, having the gun pull anywhere would indicate that it’s being held wrong or that the magazine is ludicrously heavy to have enough inertia to affect the point of aim on the X axis. Did I mess up?

  2. I’d like to see a comparative review of the 1944 Johnson LMG. Just to see if any changes were made, besides the change to a tubular butt stock.

  3. Rather like the Stoner 63 LMG in that it only had limited issue but was well regarded by its users.

    The one downside I can guess at is the rather large side mounted magazine which must have been a bit of an obstruction on the move. If it had been designed as a double column design it could have shortened the mag, it also looks a bit susceptible to damage that could cause a mis-feed, though I admit this is completely speculative.

    I had a chance to handle the M1941 rifle a while back, deactivated unfortunately, & it handled really well being less muzzle heavy than other rifles of its type. How it would fare in a situation with a bayonet fixed I could only guess.

    I have read somewhere that it suffered from wear to the barrel bearings after long use though I can’t now find any reference to that, considering it was quite heavily used by Israel in what would be a gritty environment.

        • I have read nothing about the magazine position specifically concerning the Breda Mod. 1930. The integral magazine was supposed to increase reliability by eliminating vulnerable detachable magazines. Perhaps it did; the design had other reliability problems. Reloading the magazine with the stripper clip was certainly slower than any other box magazine fed LMG I know of.

          Italian Wikipedia (https://it.wikipedia.org/wiki/Breda_Mod._30) does seem to hint that the magazine may have been a problem while moving in constrained spaces:

          “Inoltre la sua meccanica molto fine la esponeva a inceppamenti per via delle condizioni estreme nelle quali normalmente lavora una mitragliatrice da squadra, mentre le numerose sporgenze presenti erano di notevole impaccio per il movimento tra la vegetazione, perché tendevano ad agganciarsi a tutto quello che incontravano.”

          It even gives a source for that assessment.

  4. I believe in past we were running thru upgrades which followed in development of this phenomenal design, namely belt feed. With that addition it would have become superior to what followed up to this day. Shame it did not happen.

  5. While working at Springfield Armory in the 60’s I had a chance to shoot a Johnson LMG. I think it was a 1941 but might have been a 1944. I shot 2 magazines worth of ammo. Hardly an extensive evaluation but it was really fun. The Armory museum had several post war development models which were belt fed. I believe there was a belt pull issue and Johnson was working on gas assist for the belt feed prototypes. I my opinion if a belt feed for the Johnson was successfully develop kit would have made a great light machine gun.

    • Very good to read your supportive comment.

      Belt fed guns often (such as FN) use advance on both strokes – up and down. Browning and many other guns do not have this feature which does not mean they are not good; but, it is of certain advantage. It started with MG34/42 and than FN took it over as theirs. In case of Johnson, it is possible that bolt assembly did not have enough energy storage in its relatively light mass.

  6. Thanks very much for this, Ian. I’ve been a fan of the Johnny gun for a long time, and it was great to get a detailed look at it. I’ll have to bump up my support level, this one report justified my whole year of patronage.

  7. Purchasing the Johnson LMG was panic buying by the colonial government in Batavia (now Jakarta, Indonesia). The main rifle at the time was the Dutch Hembrug version of the Steyr-Mannliches M95. Chambered for a 6.5 mm cardridge. Wierd combo with the 30-06. It would have made more sense to built these LMGs in 6.5 or if there had been time, to rechamber the Mannlichers for 30-06.

    • You use what you can get. The standard small arms of Finnish coastal infantry for most of WW2 was Swedish M/96 Mausers in 6.5x55mm Swedish, but FN Mle D LMGs and Maxim MG 08 machine guns in 7.92x57mm Mauser, although they did also use the Swedish M/21 LMG in 6.5x55mm (another BAR development).

  8. I had read somewhere, that the reason the SSF got the Johnson as their LMG was because the Canadians, with experience of the Bren, did not like the BAR and made constant disparaging comparisons between the two. The Johnson was seen as more LMG like and more like the Bren, so it was given to the SSF to get the Canadians to shut up about how the Bren was better than the BAR.

    Likely just a chauvinistic Canadian “war story”, the explosives/machine gun trade with the marines sounds more plausible.


    • FSSF was Canada’s only army foray into “special ops” in WW 2. Given it saw less action than any other infantry unit that saw combat (other than the two battalions wiped out at Hong Kong in 1941)it generated a huge amount of media interest. Thanks to William Holden I guess and whichever FSSF officer thought up the “Devil’s Brigade” nickname.

      Luckily FSSF never conducted the poorly thought out and certainly suicidal operation it was created for- parachuting into Norway to destroy heavy water facilities (USAAF B-17s did the job instead). It never conducted “special operations” or parachuted into combat and was used as infantry until it was disbanded in late 1944.

      • Your info is incomplete and incorrect.
        The “Devil’s Brigade” or “Black Devils” was a name given by the Germans.
        The FSSF did in fact participate in large scale special operations, similar to how Rangers were used, look up their attack on La Difensa.
        Also, they were not created specifically to attack heavy water facilities, but yes to operate in Norway. Different Commandos did in fact parachute in and attack at Vemork, and the B-17s caused minimal damage after the fact.
        As far as “less action” goes, that is an entirely subjective statement. Though in existence for a shorter time than other units, all of the FSSF actions were intense and combat heavy. When comparing that to a unit that served the entire war, but was in less intense combat, you are drawing a conclusion that is difficult to support.

  9. Seems to be some definite AR10/15 similarities in more than just the barrel extension. Great vid.

  10. I have read several books and/or memoirs from FSSF. A frequently repeated story is that the Johnny gun on single had a sonic signature close enough to the M-1 which allowed FSSF troopers to trick the enemy by firing 8 rounds,pausing,firing another eight then switching to full auto to catch anyone who broke cover. Anyone know if this be truth?

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