RIA: Nambu Type 96 & Type 99 LMGs

The Type 96 and Type 99 Nambu light machine guns were arguably the best LMGs used by any nation during WWII – they were light, handy, accurate, durable, and reliable. Designed by Kijiro Nambu to replace his 1922 Type 11 LMG (which was fed by a unique hopper mechanism using 5-round rifle stripper clips), the Nambus are often mistaken for copies of the Bren gun. In fact, the mechanical operation of the Nambus is quite distinct from the Bren; they simply share an external resemblance.

The Type 96 was adopted in 1936 and was chambered for the 6.5x50SR Japanese cartridge. This relatively light cartridge allowed the gun to be smaller and lighter than many contemporary LMGs. All of the guns were made with rails for detachable optics, and used 30-round box magazines. In 1943 production of the 96 ended, as it was being replaced by the Type 99. The 99 was basically the same gun but chambered for the larger 7.7×58 cartridge.

The biggest difference between the two was the barrel changing mechanism. The Type 96 had a simply lever to throw to release the barrel, where the 99 has a nut to tighten the barrel down to the receiver. In addition, the 99 barrels had to be headspaced to specific guns with thin washers, whereas the 96 barrels were universally interchangeable. This change was made to reduce machining cost on the barrels, although it is often misunderstood today as being some sort of adjustable headspace device.


  1. I find it strange that one of if not the worst pistoles ever made shares the same name as one of the best light machine guns ever made.

      • The Type 94 pistol was a side arm, not a main arm. It does serve well in cramped places, where the exposed trigger sear won’t likely be much of a problem. And by the way, the rumors of that pistol being a “suicide gun” or “I surrender, suckers” gun are totally false.

        • The Type 94 Nambu pistol was originally designed for commercial sale. Most people not familiar with Japan’s modern history do not know that by the 1930’s there was a substantial expatriate Japanese “colony” in South America, with communities in Peru, Ecuador and Chile’. The home country’s industries manufactured a lot of “consumer goods” for sale in those communities because local industry did not provide same.

          Firearms were part of this, as you might expect in what were predominantly farming areas. Murata made single-shot, bolt-action shotguns in .410, 20, 16 and 12-gauge, and apparently some sporting rifles in .22 LR, 7.65 and 7 x 57 Mauser, and possibly other calibers, which would have obvious applications in such an environment. (Note that the calibers were “Western” ones, those being common in Latin America.)

          The Type 94 was apparently intended as a sidearm for local police in those communities, which would also encompass the officers of local militias. Its adoption by the Japanese military during the war was simply because they needed more sidearms, and it was already in production and chambered for the standard 8 x 21mm pistol cartridge.

          The external sear bar, aka “suicide trigger”, was simply a bad design feature, not a deliberate “trick” item. As I understand it, the pistol was supposed to have a sheet-metal sideplate covering that, but it was deleted in the prototype phase because it was found that in a humid climate (such as in its intended “market”), the sideplate collected condensation inside, thus promoting corrosion of the searage.

          Incidentally, the Type 94 was most often issued to Japanese Army and Navy aviators rather than ground or sea service officers. This was due to being a bit more compact than the Type 14 (18.3 cm OAL w/9.65 cm barrel vs. 22.9 cm w/11.9 cm barrel), as well as substantially lighter in weight (755 gm loaded vs 900 gm empty for the Type 14). Its 6-round magazine vs 8 rounds for the Type 14 was not considered a handicap for a flyer, who would rarely need to fire it and even then would probably need only two or three shots at a time.

          As with the Type 14, power wasn’t much to write home about. With a 6.6 gm bullet at ~305-325 M/s, the 8 x 21 round is about as powerful as a .380 ACP (6 gm @ ~275-310 M/s), and not far ahead of the .32 ACP (5 gm @ ~305 M/s).

          The major mystery about the 8 x 21mm round is why Col. Nambu & Co. thought it needed a locked-breech pistol action to begin with. It seems well suited to a straight blowback, much like the 9 x 20 SR Browning aka 9mm Browning Long.

          In fact, in 1942-43 a Col. Yato, while working at the Hamada rifle works, designed and prototyped pistols in 7.65 x 17SR Browning, and 8 x 21mm, intended to be mass-produced more quickly than the Nambu designs. Both were straight blowbacks based on the Browning 1910 design internally. The 8mm version, dubbed the Kenju Shiki II, was adopted for service and some 500 were made by Nagoya arsenal from mid-’43 to the surrender. With a 9.45 cm barrel, an OAL of 17.65 cm, and a loaded weight of 750 gm (6-shot magazine), it was even less bulky than the Type 94, and was a nearly perfect analogue of the Italian Beretta Modello 1934 (.380 ACP) and Modello 1935 (the same pistol in .32 ACP).



          • I seem to recall that the Yatos never quite got the bugs worked out, with some of them showing signs of premature opening. The ones I’ve seen have lightening cuts on the slide, and perhaps too much mass was removed to provide the necessary degree of inertia.

          • “Its 6-round magazine vs 8 rounds for the Type 14 was not considered a handicap for a flyer, who would rarely need to fire it and even then would probably need only two or three shots at a time.”
            Luftwaffe issued .32 Auto (.32 ACP) automatic pistols as they were lighter and more compact than 9×19 chambered fire-arms.

  2. So Bren vs. Jap 99, what to buy? They are both very nice guns and FWIW the 99 here (SN 673) shoots great. The Bren has the glitz and glamour for the collector market but the 99 is a great buy at about a third of the cost of a Bren. The 99 is under appreciated as are all Japanese guns but I agree it is excellent.

    This seems like a good time to put this out there. PLEASE do not shoot surplus JAP ammo if you value your gun! In some cases, the nitrocellulose degenerated into nitroglycerin and will explode. My dad found this out the hard way when he was pulling bullets and one exploded in the impact puller.

  3. Is there a primary extraction device or function in these guns?
    I doubt it if they are up to the reliability (and accuracy) standard of the Bren, which I am familiar with in the 7.62 NATO incarnation, less so in the original .303. You could also point out that the Japanese 7.7 mm is a development of the .303, the rifle version was, I believe, rimless. As they copied the Lewis for aviation use, they copied the ammo, and then worked on it for rifles, which were not produced in any great number. Changing standard calibers in the middle of a war is not easy, and their army/navy rivalries didn’t help.
    Fantastic video, congratulations!

    • Справочник по стрелковому оружию иностранных армий (1947) states that most common cause of failures in this machine gun is too much grease.

      • “their army/navy rivalries didn’t help”
        Yes, for me it looks like Army is too proud to use Navy cartridge and Navy too proud to use Army cartridge. In fact 7.7 Japanese might be understand as 7.7x56R Japanese Navy or 7.7×58 SR Arisaka Mod. 92 or 7.7×58.
        But this separation not only applied to hand-held fire-arms but also aeroplanes – it is normal that Navy has their own carrier-based aeroplanes but IJN posses also own 4-motor heavy land-based bombers – G8N (Rita in American code). Try to imagine US Navy running their own bomber different but roughly equal to B-24 Liberator.

  4. I have always had a love/hate relationship with all top-feed machineguns but I liked the Type 99 because they had a 2.5X offset scope that negated the magazine/ obstructed vision problem. However, the top-mount magazine is an advantage in that you can keep your head lower while firing unlike the M-14 et. al. with their bottom-feed mags. As for the 7.7 mm, I think everyone already knows my opinion of that round. A school-days friend’s father had a run-in with one of these in WWII and was hit 7 times in one burst on Saipan. He often said that this was the most feared weapon the Imperial Forces had next to the Type 99 Arisaka sniper rifle in the hands of an experienced sniper. I had the good fortune of shooting both the Type 96 and 99 during Anti-Gorilla Warfare training in the Marines and the 99 was a real joy. My two remaining objections were the open bolt action and the fact that they would not let me bring it home with me.

    • I’m glad you appreciated the Nambus, Bill. There are way to many “super patriotic” nut jobs who stereotype the IJA’s weaponry as “rip-off-stolen-design rifle, broken machine gun made by little kids, suicide pistol, and cheap ass sword.” Nambu wasn’t the best arms designer but he did make effective weapons given the material limits the Occidental countries had (somewhat unfairly) imposed upon Japan (and the Great Depression sadly paved the way for the IJA’s ultranationalist faction’s total takeover of the government, unless I’m totally wrong).

      The Type 96 and Type 99 could have bayonets fixed, but I haven’t heard any tales of anyone getting bayoneted to death by a machine gun, though I’m tempted to think the procedure for holding off an assault at melee range was “shoot, stab until the immediate threat is mostly dead, reload, continue shooting.”

      Any ideas to add?

  5. Some data from Справочник по стрелковому оружию иностранных армий (1947):
    Machine gun model 99 (1939 year):
    In 1936 Japanese Army adopted machine gun model 96 (1936 year) which was later modernized into model 99. These machine guns are identical except other cartridge. Most important technical data:
    parameter – model 99 – model 96
    caliber (mm) – 7,7 – 6,5
    overall length (mm) – 1180 – 1048
    barrel length (mm) – 560 – 560
    weight with bipod (kg) – 9,8 – 8,7
    magazine capacity – 30 – 30
    Rate-Of-Fire (rpm) – 700…750 – 550
    muzzle velocity (m/s) – 700 – 732
    sights scaled to… (m) – 1500 – 1500
    This book also contain drawings showing both machine gun, each fitted with bayonet.

  6. A local dealer, as of 2 weeks ago, has a Type 99 for sale. Tempting, but in his opinion it wouldn’t be the ideal MG to buy as a shooter because of spare parts.

    I’ve never shot one, but have now been lucky enough to see and handle one a little.

  7. I can’t see the Type 96 or Type 99 as being better than the Bren. The Type 96 does need oiled rounds (it may function on the range with unoiled rounds, but would any modern owner put a few thousand rounds through it in combat conditions to see how it works? Thought not).

    As for the Type 99, it is clearly a good gun, but the barrel is held on by a nut which needs a wrench to get it off, and then it needs shims to headspace properly, so you cannot call it a quick change barrel. With the Bren, a new barrel can be fitted in five seconds. So they are by no means bad guns, but I would have to put them behind the Bren.

    • Uh, the Bren was manufactured in Imperial units while its predecessor was perfected in metric units. That meant a headache for the guys at the armory from the start. Because of precision error due to unit conversion, the Bren’s magazine could only hold 28 rounds instead of the intended 30. However, you are right in that the fully-developed Bren became the paragon of light machine guns, “a standard against which all others would be judged” (reference from Roger Ford’s book, The World’s Great Machine Guns).

      The Type 99’s barrel production was done on a very strained material budget, mind you. Supposing Nambu did design that gun to have a quick change barrel in the true sense of the phrase, there would be more emphasis on getting the barrels made correctly from the start. And if a worker messed up machining the attachment point, there went another good gun barrel, and perhaps the general would have his head for that!

      • All the BREN gunners I’ve talked to (A surprising amount, perhaps. Five or six) have said that they never loaded more than 28 rounds into the magazines as spring failures were a very real concern, considering the dark times many of the weapons were manufactured in. They also said that they insisted upon loading their own magazines once they found out that when someone else who wasn’t a BREN gunner had done it, rimlock became a problem…

        None of them had anything but respect for the things, however. None of them fought up against Nambus in the Pacific (or in the Pacific at all) and sadly none of them are with us any more.

        • My wife’s grandfather used the Bren gun against the Japs in the pacific but sadly he’s not around anymore to ask about it.

        • I am not sure spring failure itself was the issue. more the shape of the rimmed .303 round in the magazine. It seemed to be that with 30 rounds loaded, the spring didn’t have quite the power to push the rounds down reliably enough, but with 28 there was no problem. The fact that when rechambered for 7.62 mm, the Bren would shoot 30 rounds without a problem suggests to me that that was the case.

  8. I had always thought Ian’s comment of wanting a 7.62×39 converted Nambu LMG was an interesting choice which i didn’t neccesarily understand albeit it seemed cool, but it really makes excellent sense now. Suddenly it becomes hard to see why anyone wouldn’t want one! I had no appreciation for just how impressive these were.

        • If Starline has .260 Remington or 6.5 Grendel brass at reasonable prices, that and a Dillon reloading machine would put you in good shape. Of course the nice thing about .260 is that it can be made from .308 or 7-08 brass.

  9. Just a few more comments. The Bren magazine springs were a liability, as were the VGO magazine springs (96 rounds rather than the nominal 100), this has to do with the quality of steel used, initially they were made from a special Swedish steel, and later had to make do with another, after the magazine dimensions had been fixed. The 7.62 mm NATO version of the Bren had a full 30 round capacity, and would feed even with blank ammunition. The ZB vz 26 originally had 20 round magazines, so the 30 round mag for a rimmed case was a challenge. Loading them is very straightforward, and you have to be a goof to get the rims crossed.
    The rate of fire of the Nambus was higher than both the Bren and the ZB vz 26, definitely an advantage in an ambush situation, but their barrel mounting is flimsy compared to the interrupted screw type lock on the Bren (and the later GPMG), and I fail to see any advantage in a scope sight for a squad automatic. After seeing a Bren perform the falling plate competition; 10 of 12″x 12″ steel plates at 300 yards(I think) in full auto, 20 rounds available, I doubt if a scope is of any benefit. If the tactical situation is to loose off 3 or 4 mags then this is fine, any real hard work I have my doubts.
    The toolkit for the .303 Bren had a round-like device to be fed into the chamber and ejected to clear remains from a separated case, this seems to have been seldom used and the 7.62 mm Nato version does not have it. In fact later versions have a chrome lined barrel and no spare barrel, what a waste of a good mounting!
    The ZB vz 26 was selected by the British to adapt to .303 and manufacture under licence. It must have been excellent in most respects, I know for a fact that the first Brens were too accurate, they just didn’t spread it about as a MG should! This was corrected, even so the accuracy of the LMG in 7.62 Nato is legendary.
    Please note that the Nambu sight is very nice but identical to the Bren Mk1 and the ZB vz 26 except for the windage. Later marks of Bren reverted to a battle sight and a flip-up ladder sight to save costs and allow a large aperture for quick use and a small aperture for precision. Zeroing the weapon was done by changing the front post for height, and moving it sideways for windage. Every barrel was thus individually zeroed.
    The gas regulator on the Bren is a bit of a pain, but I never had the need (or known of such a need) to change it during firing. You select 2 for temperate conditions, 3 for arctic and 1 for desert. Only if the gun gets seriously gunged up do you need to change, and then you do it during a barrel change. Note that the carrying handle on the Bren/LMG can be locked perpendicular to the barrel as a forward grip to fire from the hip. Useful on night patrol, take off the bipod, tape 2 mags together (another double in a pouch) and use a double length sling over your shoulder to help with the weight (if you need it…) and you’ve got 120 rounds of fun without anything rattling or making a noise.

    • The Japanese were keen on conserving ammunition whenever possible, so I suppose the low-power scope was to aid in that endeavor. The scope would allow the gunner to “zoom in” on the intended victim (who at this time is peeking from behind cover) and then percussively decapitate him… Or am I wrong?

  10. The Type 99 s have conversion kits to the more available 7.62X51 or 308 ammo. There are also very nice conversion kits available for both the Type 96 and the Type 99 LMGs that convert them to 7.62 X 39 making them very cheap to shoot. Wow cheap, reliable, with very low recoil that all adds up to more fun to own than than most LMGs.

  11. A great read of someone on the receiving end of the 96 is “Shots Fired in Anger” by Col. John George
    A gun nut at war, he stated that the 96 probably killed more than all other Japanese light arms combined.
    Walking point was a terrifying job when those weapons were hidden and dug in.

  12. A great presentation. I have always admired these guns and it is great to see them in detail. There are plenty of them in museums here in Australia, but we don’t get a chance to own them here. In accounts by the Australian military of the fighting in the Pacific, these guns are usually referred to as ‘Bren-type light machine guns’, I guess at the time people did not go into detail. It is obvious that the Japanese were wary of the Bren – during the battle for Buna, Japanese snipers brought down every Bren gunner in one battalion. Also, in the fighting on the Kokoda track, the Thompson M1928 has been given credit as a major factor in containing the Japanese advance, since they had nothing to compare with it, and the Australians had much higher numbers of automatic weapons generally. Japanese battle reports were found lamenting the effectiveness of Australian ambushes using these guns.

  13. Friends,
    I was in Tokyo in high school during the Korean War.
    I had both the Bren and the Type 99.
    I fired them both.
    I liked the Bren more than the Type 99 because I could field strip the Bren for cleaning in 15 seconds.
    The Type 99 took me much longer.
    As to combat use, I had no clue.
    I sure wish I had been able to bring them home.

  14. In answer to an earlier question above: yes, the Types 96 and 99 have primary extraction. Though the locking block travels vertically to engage a slot in the bolt, the front wall of the slot is not precisely vertical but is cut at a slight angle. Thus in unlocking there is a short and slow initial movement rearward before complete unlocking. That movement provides time and leverage to loosen the fired cartridge case from the chamber walls before extraction.


  15. The primary extraction would seem to have been insufficient if they needed to oil cartridges, perhaps a reflection on ammunition manufacturing standards? The Bren did not have oiled cartridges and had a powerful primary extraction provided by the buffer spring in the unlocking horn.

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