Abstract: An optical cartridge adapted to be used in a weapon for emission of a light signal when the weapon is fired, which cartridge includes at least one battery; a light source adapted to be energized by said battery(ies) so that a visible or an invisible light beam will be emitted; a lens system; a firing switch adapted to be operated by a trigger acting on the weapon; and control circuits which represent the required interface between the battery(ies) and the light source. The cartridge in addition includes a loading switch adapted to energize the light source to emit an alignment light beam as long as the weapon is loaded with the cartridge. The main advantage of the invention is that the shooter will obtain detailed feedback relating to the quality of the aiming process.