A priming device for a projectile incorporating a safety and arming device as well as an electrically initiated detonator that is activated by an electronic firing module, wherein the priming device incorporates a second detonator integral with a rotor or flap of the safety and arming device, the second detonator being activated by a mobile firing pin, such firing pin being arranged opposite a first detonator so as to be projected by the gases resulting from the ignition of the latter.