Abstract: A fire control system comprises a platform (10) rotatable in azimuth on which are mounted a gun (11) first and second sighting devices (15,25) each of which is movable in elevation, each sighting device (15,25) having its sight line nominally aligned with the barrel axis of the gun (11), the first sighting device (15) incorporates a lens (39) defining the sight line thereof, a graticule (41) defining an alignment mark and a mechanism (19,20) coupled to the lens (29) for alignment adjustment. Gun (11) comprises a muzzle reference mirror (12) and the first sighting device (15) incorporates a direction-finding means which is arranged to enable the position of an image in the muzzle reference mirror (12) to be identified with respect to the alignment mark of the graticule (41), the mechanism (19,20) being operable to effect alignment of that mark with the image seen in the muzzle reference mirror position.