An inertial delay mechanism for use in an explosive projectile is provided. The delay mechanism consists of an inertial delay fuse that is precise, doesn't require sensitive primary explosives and doesn't utilize electronic circuitry. The inertial delay fuse includes a free sliding charge element that strikes an anvil located opposite to the sliding charge element. A delay gap is provided between the sliding charge element and the anvil. Upon impact, the sliding charge element slides forward and impacts the anvil, thereby inducing a shock wave in an initiator charge that subsequently results in detonation of main charges. The design is mechanically simple and robust enough to withstand severe g-loading forces that occur during firing and penetration of a projectile.