A./P. Hand Grenade No. 70 Mk I (Obsolete), Mk II (Obsolescent), and III (Service), and No. 71 (Obsolete)

Over-all length

Diameter

Total weight

Filling

Fuzing

Delay

Markings

Description: The Grenade Mk II consists of a cast-iron body, a fuze adapter, a base plug with a rubber spigot, and a filling-plug hole. The body is cup-shaped and threaded internally at the top to accommodate a fuze adapter. It is closed at the bottom by a threaded base plug to which is cemented a spigot. A rubber washer is interposed be-tween the plug and the body. The adapter of zinc-base alloy is threaded internally to house a D.A. Percussion Fuze No. 247 Mk III, and is formed with a central perforation to position an aluminum detonator tube. A rubber washer is positioned between the fuze and the body. The filling hole in the side of the body is closed by means of a molding plug and a rubber washer. The body contains a filling of Baratol or Amatol.

The Grenade Mk III differs from the Mk II in that the filling hole and the thickening of the case at that point have been completely eliminated, and the Amatol or Baratol filling has been replaced by RDX/TNT 50/50, with a C.E. pellet.

Operation: The adhesive tape securing the fuze safety cap and the cap itself are re-moved. When the grenade is thrown a weighted strip of tape withdraws the safety pin to arm the fuze. On impact, the striker overcomes the creep spring, and fires the cap, which initiates the detonator, and, in turn, the main filling.

Remark: The Grenade No. 70 Mk I was allocated to a small number of experimental designs not issued for service use.

The Hand Grenade No. 71 was a larger grenade of the same type constrcution as the No. 70, weighing approximately two pounds. The Grenade No. 71 was never adopted for service use.