Murray Mk 1 Booby Trap Switch

Switch, booby trap, combination Murray Mk 1 (Aust.) as used by the Australian Army during the Second World War. The switch consists of a hollow cylindrical body made from die-cast metal with a screw cap at one end, inside of which is a steel plunger and spring. Operational components are made from steel.

This booby trap ignition device was developed by VX80915 Major Cyril Stewart Murray, of North Brighton, Victoria in 1943 and submitted to the Army Inventions Directorate. Following further development of this switch, Murray received a 1,000 Pounds reward on 11 October 1950 for this invention. The switch is designed to operate in three positions. 1) Push position, by the application of a weight or blow. 2) Release position, by the displacement of a weight or object. 3) Pull position, by a pull of a trip wire or cord. In each of these positions the operation of the trap causes the release of a spring loaded plunger, the pointed lower end of which detonates the cap of an empty .303 cartridge case held in position by a collar engaging the rim of the case and screwing on to the trap body. Detonation of the primer cap ignites the safety fuse which is held in position by being clamped between two small lugs cut in the end of the cartridge positioned in the screw cap. The switch can be placed into various objects which, when removed or pressed, will operate the trap. This booby trap device was used extensively against the Japanese in New Guinea and the island campaigns, and saw continued post war use.