Type 3 grenade

The Type 3 "anti-tank" hand grenade is a Japanese grenade produced from 1943 to 1945 during World War II. It was designed to destroy the Allies' tanks. There are three variants (sub-types) of the weapon: Ko (Type A), Otsu (Type B), and Hei (Type C).

History
Throughout World War II, the U.S bombings gradually degraded the Japanese munition manufacturing base. Manufacturers were soon forced to find new, inexpensive and creative ways to produce grenades. Contrary to the Russians or Germans, the heavy armour threat was not very present, thus explaining the late development of the hollow charge. The Type 3 had a simplistic design and was made from expendable materials. This made the weapon relatively easy to produce.

Examples of this Japanese grenade are extremely hard to find today.

Design


The Type 3 grenade had a tear drop-like shape. It consisted of a thin steel or aluminium cone mounted on a wooden head. The purpose of the head was to provide the correct stand-off distance when the weapon detonated, as shaped charges are ineffective if they detonate too close to the target. The explosive was cast around the cone and covered by a cloth bag made of either silk or hemp twine.

The upper extremity was made of a very basic impact firing mechanism, that detonated the grenade if it struck a hard surface at a speed of around 40 ft/s. A tail made from hemp strands served to stabilize the grenade in flight, and ensured the target was struck successfully. The grenade would be used by first removing the safety pin, then throwing it by hand from a distance of around 10 meters.

The grenade had a penetration power of 70 mm. This shows that it exceeds the penetration of the Type 99 magnetic grenade.

Sub-Types
There were three official variants of the Type 3 hand grenade:


 * Ko (Type A): This variant had a length of 17.3 cm, a diameter of 11 cm and a weight of 1.27 kg. The explosive filling was 0.853 kg of RDX/TNA. The colour of the outer cloth covering was either white or brown-yellow.
 * Otsu (Type B): These had a length of 14.8 cm, a diameter of 10 cm and a weight of 0.853 kg. The explosive filling was PETN and TNT with a weight of 0.69 kg. The outer covering was either white or brown-yellow.
 * Hei (Type C): This variant was identical in size and weight to the Otsu Type B, however the explosive filling was Picric acid. The colour was yellow.