Hydrodynamic firing pin

In combination:

• an explosive propulsion member having an axial percussion primer;
• an electric primer mounted to discharge toward said percussion primer along the axis thereof;
• a safing mechanism between said primers including a radially contained body of highly viscous material;
• and means mounting said mechanism for movement transverse to said axis between a first position, in which said body is on said axis, and a second position, in which said body is displaced from said axis, so that when said mechanism is in said first position and said electric primer is discharged, said body is hydrodynamically propelled against said percussion primer to cause it to fire.