Abstract: A novel detonator is equipped with an instant-trigger primer element. The detonator can be triggered mechanically and provides rapid ignition of the delay charge. In this manner, misfires are avoided which occur due to the fact that in case of an only slight impact, a spring-loaded firing pin is again pulled out of the detonator even before igniting the delay charge and can render the detonator useless because of pressure relief. The primer element contained in the detonator exhibits an outer casing into which is embedded, in a shape-mating fashion, an inner casing so that the bottoms of both casing are placed in mutual superposition in such a way that a cavity is formed between them, this cavity being furthermore defined by the sidewall of the outer casing. This cavity houses the primer charge which is to contain, besides the usual oxidants and reducing agents, rapidly acting initiating explosives. A directional ignition jet is produced by a special configuration of an ignition duct.