
The Tail Hydrostatic Fuze Mk 231 Mod 0 and Mk 240 Mod 0 are tail hydrostatic fuzes in the general design scheme of the Mk 229 and Mk 230. They are considerably simpler in construction, however, and easier to manufacture. The Mk 240 Mod 0 is four inches longer than the Mk 231 Mod 0, to assure proper arming in larger bombs, but is otherwise identical to the Mk 231 Mod 0. A single depth setting is provided. and the fuzes are expected to function in a depth range of 25 to 30 feet.
To provide positive action against fuze function on reverse impacts (particularly ricochets), these fuzes have an inertia ring which adds its weight to that of the piston assembly to counteract the force of the two counterbalances exerting a contrary pressure in such impacts. On normal impacts, the inertia ring merely rests on the firing-pin housing.
The Mk 240 Mod 0 will not be produced at all.
No information about functioning.
No information about hazardous components.
Tail, Hydrostatic, AN-Mk 230 Mod 3 - 6
OP 1664, Volume 2 - US Explosive Ordnance (1947)
USNBD - Bombs and Fuzes, Pyrotechnics (1945)