PIBD, M530, M530A1
Point initiating, base detonating type Fuzes M530A1 and M530 are designed for use in low-velocity HEAT projectiles.
The fuze is essentially an aluminum housing containing a spring-loaded brass rotor and an electrically fired detonator. In the unarmed position, the rotor is restrained by three metal leaves, so arranged as to be displaced sequentially by inertia from setback. The power source is a polarized piezoelectric ceramic disk (not shown) in the nose of the projectile connected by a wire lead to the fuze. A separate inertial plunger with firing pin is provided to act on the primer for graze impact.
Model M530A1 includes an escapement mechanism not present in Model M530 to retard the rotor and extend arming time.