Abstract: An electromagnetic projectile launcher (commonly referred to as a "railgun") consists of an electrical direct current power supply, two parallel rails (52), and switching armature (54) releasably linked to a projectile armature (56), each armature being slideably located in mutually parallel channels between and along the length of the rails. The rails are each provided with two overlapping conductive zones along their length, the first zone (60) being electrically connected to the power source and in electrical contact with the switching armature in its start position. In operation, electromagnetic forces induced by the power supply propel the switching armature (54), and hence the projectile armature (56) linked to it, along the rails from the start position until the projectile armature comes into electrical contact with the second conductive zone (62).