At the beginning of the War in the Pacific the Imperial Japanese had a number of portable infantry weapons that could be used against armor and vehicles, but many of these were developed during the interwar period. As a result most were obsolete by the time the Allies began their push back in WW2. The majority of the anti-armor capable portable weapons Japan had at hand were only effective against trucks, older light tanks and improvised armor used by the Chinese, and various armored cars such as those used by the Soviets. To be sure, for the most part these weapons were designed for anti-infantry use, to break bunkers, machine gun nests, and buildings that Chinese forces might use for cover. Heavy mortars were also used to take these out, and could perhaps be considered the favored weapon for an assault on fortifications. But the Chinese and other enemies of Imperial Japan did have armor of their own, so anti-armor capabilities were not ignored entirely, even in the 1930s.
Among those weapons from the interwar period capable of serving in an anti-armor role were the Type11 37mm Infantry Gun (shown in the interwar photo above with shield) which had a marginally effective anti-tank shell and the Type92 Heavy Machine Gun (also shown) which could use brass bullets with steel cores for armor-piercing. Even the Type38 Arisaka Rifle, which had a design dating back to the time of the Meiji Emperor in 1906, had Type92 7.7mm “armor piercing” rounds, but it was hardly a modern anti-tank weapon. Also used in an anti-tank role was the 70mm Type92 Battalion Gun (also known as the M92 Light Howitzer), but again this was not a pure anti-tank weapon. While these could be used to effect against landing vehicles like the American LVTs which had light or no armor, or armored cars like the Soviet BA-3/6, they were ineffective against newer Allied tanks.
Japan’s anti-tank guns were powerful enough to be effective against light tank armor including Allied light tanks such as the M2A4 and M3 Stuart, and included the Type1 47mm AT Gun of which roughly 2,300 were made. But most AT guns required trucks or prime movers / artillery tractors to move from place to place. Of particular interest to wargames such as fast-paced RTS or even miniatures wargames are portable “hand held” weapons that can be moved easily around a large battlefield or jungle without mechanized assistance, hitching, and unhitching.
Mobility of these weapons (and no doubt cost) was important to Japan as well. Several “hand-held” weapons were developed to counter Allied armor, and at risk of life and limb, some could penetrate the armor of a Sherman tank (listed in order of introduction):
Type99 Magnetic Mine – The so-called “tortoise mine” from 1939 was actually more like a sticky grenade, and was kept in a fabric bag. It was meant to be thrown at enemy armor, where it would self-attach and detonate. Some American troops used wooden planks attached to the sides of their tanks to defeat the mines. These were effectively replaced by the Type3 HEAT Grenade.
Type2 40mm Anti-Tank Grenade Launcher – This “grenade launcher” from 1942 was actually a (somewhat rare) attachment that could be used on a Type38 or or Type99 Arisaka rifle to fire grenades. The older Type 100 Grenade Discharger attachment could also fire grenades (common “Kiska” fragmentation grenades), but the Type2 was unique for allowing anti-tank grenades to be fired. Japanese sources claim the 40mm anti-tank grenade could penetrate up to 98.552mm of “mild steel plate.” Apparently one of these examples was captured by U.S. troops, but it seems field use of this weapon was limited.
Type3 HEAT Grenade – This was a crude-looking design that looked a bit like a gourd in a burlap bag, perhaps because it was a late war Japanese weapon meant to use minimal resources. It had rather impressive armor penetration of 70mm, however and should see more use in games.
Type4 70 mm AT Rocket Launcher – Comparable to the U.S. Bazooka but with angled venturis in the base to spin the rocket for stability instead of fins, these AT weapons, first deployed in 1944, came too few and too late to stop the U.S. Sherman onslaught, but would have been useful to Japan in large numbers.
A major problem with many hand-held AT weapons was one of range. A Sherman tank could shoot much further than a man could lob a weapon. Doing so often meant exposing oneself to immediate retribution. Some desperate Japanese units late in the war turned to the suicidal tactic of carrying shaped charges on poles which would be rammed bayonet-style into the side of a tank. The penetration estimates for these were quite high, but they also were almost sure to result in the attacker being impaled on the pole or killed by the resulting explosion. This would not have been an officially sanctioned practice. and the pole weapons would have been field improvised.
Note: Some wargaming sources will show early Japanese units at war using anti-tank pole charges as a part of their standard arsenal. This is not accurate, and plays to stereotypical images of Japanese troops. Imagine being the fellow in the background of the Italeri model kit box art image above with a pole charge, knowing that everyone else in your unit has a chance to fire from range except you! Of course the cover art is just to give an idea of the full range of weaponry, but still… The pole charge idea should be reserved for last-ditch defenses in the same spirit as a final Banzai Charge, or used from a Spider Hole (see “doctrinal abilities“). It is unlikely that Japanese troops at Nomohan, for example, would have all been running around with AT pole charges to assault Soviet Tanks, as can be seen in some wargaming miniatures. They were not quite at that level of desperation, though Japanese troops are often cited for making “suicidal” charges. It is also unlikely Japanese troops would designate “human bullets” to go out with pole weapons before they had expended all of their existing ranged anti-tank weaponry / ammunition.
Type97 20mm Anti-Tank Rifle
One of the more interesting weapons developed by Japan during the interwar period (1937) that did not have the problem of range was the Type97 20mm Anti-tank Rifle which could be used from a much longer distance in a sniper-type position.
The rifle itself was huge at about 60kg or 150 pounds, and 9-10 soldiers were required for efficient operation of the weight in the squad, just as if a wounded comrade was being carried on a stretcher. It was an expensive design as anti-tank rifle, the price of this gun at that time was 6,400 yen . By comparison the old Type38 Infantry Rifle was only 77 yen. As Japan did not have unlimited resources, these anti-tank rifles were deployed only where it was felt they were absolutely required, such as against Soviet armor at Nomohan. They were also reportedly used by Imperial Japanese paratroopers, which would have given them an additional punch behind enemy lines.
Armor penetration was 30 mm at 90° at 250 metres. That level of penetration would have the ability to potentially damage M2A4 U.S. tanks used by the Marines in the battle of Guadalcanal, for example, which had a maximum thickness of 25mm of armor, or pinpoint penetration of an M3 Stuart which had some spots with only 13mm of armor.
A downside to the rifle was that it was difficult to manage because of its bulk and weight and getting a good shot at moving targets would have been challenging. Beyond that, even with armor penetration a “hit” to any personnel inside the tank or critical interior components would have been a matter of luck or extensive knowledge of the targeted enemy vehicle since the bullet was relatively tiny compared to, say, a 37mm tank shell. That said, the Type97 HEAT ammo it used was high-explosive, and well-aimed shots even without penetration of the hull could have been used to break a tank’s track pin, damage a sprocket, or “stake” a turret from rotating or its main gun from elevating.
The Type97 AT rifle would have been an excellent support weapon against armor, but infantry would have been in a difficult spot to rely on the rifle alone against a tank or group of tanks. It would have been more useful against light armor such as that of the Soviet-built BA-20 armored scout car used in the battle of Nomohan. The 6mm thick armor of that vehicle would have been easily penetrated by the Type97 AT rifle, and the position of the driver at least was obvious enough.
Chambered for the powerful 20x124mm cartridge, the Type 97 is a magazine fed, gas-operated weapon that fires from an open bolt. More like a small artillery piece than a traditional self-loading rifle, the whole receiver and barrel assembly of the Type 97 actually slides front-to-back during firing.
When fully assembled with its armor shield and carrying handles, the gun weighed in at an astonishing 150 pounds. The barrel, which could be removed for long distance transport, was locked to the receiver using an interrupted thread mechanism.
Once the gun had been carried to its destination, the crew would adjust the three legs and lower the weapon into its firing position. To cock the weapon, the charging handle located on the left side would have to be pulled fully to the rear, with a loud “click” letting the shooter know that the sear had engaged the bolt carrier. After ensuring that both dust covers were open, a loaded magazine would then be locked into place on the top of the gun. At this point, the gun was ready to fire.
The following ammunition was available:
- Type97 HEAT (High-Explosive Anti-Tank) armor-piercing bullets
- Type97 HE Howitzer bullet – For soft targets, with a high-explosive agent chamber inside the casing, located in the bullet base. Uses a Type93 small explosive detonator.
Per Japanese sources on combat use:
“As an early combat early example from 1939 during the Nomonhan incident it was quite useful to some extent the few were used in. It proved itself against armored vehicles in particular. The documentation of the Soviet side, has been described as including 20mm guns of the Japanese army side, but there was no record that the Japanese army has deployed any troops with a 20mm machine gun at Nomonhan, so it is believed the Type97 damage to their tanks and armored cars was what was the Soviets actually witnessed.”
The Type97 AT Rifle in the game Men of War Assault Squad – Unlikely that anyone but the strongest Japanese man on earth could have fired the weapon standing up, and even then the recoil would have knocked him off his feet! A Type3 Heat Grenade can also be seen in the soldier’s inventory, bottom left.