Type of explosive: Solid ring main charge of cast picric acid with inner ring booster of pressed powdered picric acid containing a central hole 5/8 inch diameter to house fuze. Explosive completely covered by layer of paper, shellacked to the explosive and waxed externally.

Color and markings: Olive-drab with narrow red ring around brass plug. Mine may have numerals (such as 16.9) in white on top indicating date. meaning safe inscribed on top of safety cap and on lug of safety washer.

Description: The mine is circular with a slightly domed top and flat bottom. It is con-structed of an upper and lower section of sheet metal secured together by four heavy corrugations in the walls which serve as threads. The overlap of the walls of the two sections is sealed with a bituminous paint. The interior of the container is painted with a black enamel. Soldered on the inside of the bottom of the lower section is a brass disc 1 9/16 inches in diameter, having a threaded collar for the insertion of the fuze.

The central hole in the upper section is reinforced with a brass collar threaded to receive the brass plug. A thin leather washer fits between the brass plug and the collar to seal the mine.

Two brass rings are fastened to two opposite sides of the upper section by means of a soldered metal strip. Drag ropes may be fastened to the rings.

The fuze assembly consists of a striker held striker spring pressure by a shear wire, a percussion cap, a primary detonator, and a larger secondary detonator all incorporated in the fuze body which is threaded on the lower end to screw into the collar in the bottom of the mine. A safety cap is screwed into the upper end of the striker until the mine is laid. An additional safety feature is a brass cylinder with attached washer which fits over the brass safety cap and rests on top of the fuze body, the washer fitting under the leather washer of the brass plug.

Employment: Antipersonnel and antitank. The Japanes have two sizes of shear wire for this mine. One for antipersonnel use shears at 70 pounds, the other, for antitank use shears at 250 pounds. These mines have been found buried upside down with additional explosive placed beneath them to increase their effect. The A/P fuze has a black upper body.

Operation: With the safety devices removed, any load on the cover of the mine causes the brass plug to press down on the striker. If the pressure is sufficient, the shear pin is sheared. This frees the striker which, under pressure of the spring, strikes the percussion cap initiating the detonating system.

Figure 152 – Type 93 Anti-Tank and Anti-Personnel Land Mine.