A device for setting mechanical time fuse in which the fuse has an element which, when rotated, adjusts the time period of the fuse. The fuse is contained within a housing at the forward end of a projectile and within the housing forwardly of the fuse is a stepping motor connected to the rotatable element of the fuse by reduction gearing. A setting device in the form of a pulse emitter and adjustable logic circuitry is disposed outside the firing tube in which the projectile is mounted and is electrically connected with the stepping motor by wires which include separable connectors. The setting device advantageously provides for ignition of the projectile propelling charge when the setting of the time period for the fuse has been completed. Also, advantageously, a clamping device is provided for clamping the stepping motor in its adjusted position prior to or immediately upon ignition of the propelling charge.