Description: The internal design of this device closely resembles that of the Japanese Navy C-1 (a) tail fuze. The bakelite outer casing houses the mechanical parts of the in-ternal assembly. This internal assembly can be divided into three primary sections. The top section is the plunger, which has a locking detent in its side and is fitted on the bot-tom with two spikes for piercing the solvent tank. A safety fork, which is inserted through the outer casing and the plunger, prevents accidental depression of the plunger and the consequent starting of the delay action.

The central section contains the solvent tank, striker spring, striker, striker detent, and soluble plug. The upper end of the striker spring bears against a stud on the plunger while the lower end bears against the striker. The striker is held in the unfired position by the striker detent which is in turn held in contact with the grooved striker body by a so-luble plug.

The lower section houses the firing train whose components are a primer, a pressed black powder delay train, a gain from a 25-mm projectile fuze, and a tetryl booster.

The delay time of this device is not known as the solvent ampoule was not recovered. The purpose of the black powder delay train is also not definitely known.

Employment: Not known.

Operation: To fire, remove the safety fork and depress the plunger. This action causes the spikes on the plunger to pierce the solvent tank and release the solvent. The de-pression of the plunger also compresses the striker spring. The plunger is locked in the depressed position by the detent in its side which engages a notch in the outer casing. The solvent softens the soluble plug allowing the striker detent to be cammed outward to free the striker. The compressed striker spring forces the striker into the primer initiat-ing the firing train.

To render safe: Destroy in suit if possible, otherwise remove device from charge and dispose of it immediately.

Figure 194 – Chemical Delay Firing Device.