Type 100

Type 100/40 and 100/44. Japanese submachine gun Type 100.
History, development, service, specifications, statistics, pictures, and 3D model.

Japanese submachine gun Type 100

Type: Japanese submachine gun.

The Type 100 submachine gun was a Japanese weapon used during World War II.

Overview

Development: It was developed in 1938-1939 and entered service in 1942.
Design: The Type 100 was based on the German MP18/MP28 design but with some unique features.
Caliber: It fired the 8mm Nambu pistol cartridge, which was relatively weak compared to other submachine guns of the era.
Rate of fire: Approximately 450 rounds per minute.
Variants:
– Type 100/40: The original model
– Type 100/44: A simplified version for easier mass production
Features:
– Side-mounted magazine
– Wooden stock and foregrip
– Blade front sight and flip-up rear sight
– Bayonet lug for attaching a sword bayonet
Capacity: 30-round box magazine
Effective range: About 150 meters
Production: Relatively limited, with only about 30,000 units produced
Usage: Mainly used by paratroopers, naval landing forces, and special forces
Performance: Generally considered less effective than contemporary submachine guns due to its weaker cartridge and lower rate of fire

The Type 100 was not widely used compared to other Japanese small arms during World War II, but it did see action in various Pacific Theater campaigns.

History

Sub-machine gun development in Japan was curiously neglected until about 1935, after which an experimental model was produced and tested. But there appears to have been little enthusiasm for the weapon, which, considering that Japan was by then engaged in a war with China and preparing for war throughout the East, is most surprising. The sub-machine gun would have been an ideal weapon for them, and the thought of the Japanese Army armed with a cheap and simple sub-machine gun such as the Russian PPSh is quite terrifying; the combat in the Far East would have been a good deal more bloody, and one or two touch-and-go affairs might well have gone the other way.

The Type 100, Model 1940, was issued in 1941-42 in limited numbers. It was a modified Swiss Solothurn S1-100, which was also used by the German and Axis armies in Europe. Although far from perfect its performance was good enough to stimulate interest in the weapon, and this led to development of an improved version, the Model 1944, but work began too late and was carried out too slowly to allow stocks to be built up.

The Model 40 came in two patterns, one for infantry use with a solid stock and one for Airborne troops using a hinged folding stock. Both were fitted with bayonet bars under the barrel, and the interior of the barrels was chrome plated. The infantry models were sometimes fitted with a small bipod. Mechanically there was little of note; they were a simple blow back weapons working on familiar principles.

The only recorded use of these weapons in combat was in the Japanese parachute attack on the Dutch oilfields in Java in 1942, when they were reported to have been highly effective. There is no record of their appearance against US forces in the South Pacific nor against British troops in Burma. It is believed that less than 10,000 of both models were produced.

Variant

Type 100/44: Mechanically the same as the 100/40, this had a weaker recoil spring which increased the rate of fire to 800 rpm. The bayonet bar was removed and the bayonet attachment was by two lugs on the barrel casing. The muzzle was formed into a compensator by drilling two lateral holes. There were other small changes intended to make the weapon easier to manufacture. It is reported that about 7,000 were made in the last year of the war, but none of them appear to have reached the hands of troops.

Users: Japan (for all variants).

---

Animated 3D model of Japanese sub-machine gun Type 100

---

Specifications Type 100

Specifications:

Type 100	Specification
Type	Sub-machine gun
Caliber	8 mm
Length	35.0 in
Weight	8 lb 8 oz
Barrel	9.0 in long, 6 grooves, right hand twist
Feed system	30-round detachable box magazine
System of operation	Blowback, selective fire
Muzzle velocity	1,099 feet/sec
Rate of fire	450 rpm (Model 100/44: 800 rpm)

Service statistics:

Type 100	figures
Manufactures	Atsuta Ordonance Factory, Nagoya Arsenal
Production delivery	1941
Final delivery	1945
Production figure	c. 17,000 (incl. 7,000 of Type 100/44 in 1945)
Price per unit	unknown, but not designed for ease of production

---

References and literature

The Encyclopedia of Weapons of World War II (Chris Bishop)
The Encyclopedia of Infantry Weapons of World War II (Ian V.Hogg)
Infanterie im 2. Weltkrieg (J.B.King, John Batchelor)
Illustriertes Lexikon der Waffen im 1. und 2. Weltkrieg (V. Dolinek, V. Francev, J. Sach)