Descriptions: This grenade is designed to be launched from a spigot type rifle grenade launcher on the type 38 or type 99 Japanese rifle, using a cartridge having a wooden bullet.

The grenade is of light, seamless, steel construction and has an incendiary filling of white phosphorus. The nose piece is threaded at its forward end to receive the fuze. A thin, metal well extends into the filler and is soldered around the fuze pocket to give an air tight seal. This well contains the detonator and auxiliary detonator of the fuze, which serve as the bursting charge for the grenade.

The barrel of the grenade is threaded at its forward end to take the nose piece, and at its after end to receive the hemispherical end plate internally and the base piece exter-nally. The end plate has a smaller hole in its center. The base piece is threaded at one end to screw onto the barrel and at the other end to screw into the stabilizer tube. A bakelite cushion is cast into the base piece to fit the hemi-spherical end plate.

The stabilizer consists of a cylindrical tube which threads onto the base piece. Four fins are welded to the after section of this tube at 90° intervals.

The rolled threads, joining the barrel and base piece and stabilizer, are reinforced by wrapping and soldering soft iron wire into the thread grooves.

The fuze used in this grenade is the same as that used in the type 97 hand grenade.

Operation: After the grenade has been placed over the spigot adapter of a rifle loaded with a cartridge having a wooden bullet, the safety pin is removed from the grenade. When the rifle is fired, the gases from the cartridge propel the grenade, and the force of setback initiates the grenade fuze. After a short delay, the fuze detonates, rupturing the case of the grenade.

Figure 185 – Small Icendiary Rifle Grenade.