Abstract: A front-loading mortar mounted on a base, such as the top of an armored vehicle, includes a weapon tube having a muzzle; a trunnion axis about which the weapon tube is pivotal for setting an elevation of the weapon tube; a cardan ring surrounding the weapon tube or cradle tube and being circumferentially displaceable about the weapon tube relative thereto; an additional pivot axis defined in the cardan ring at a location situated in front of the trunnion axis; and a loading manipulator, including a loading tray, for moving a round of ammunition to a loading location in front of the muzzle. The loading manipulator includes a loading rocker articulated to the cardan ring for pivotal motion about the additional pivot axis; an elongate positioner articulated to the cardan ring for pivotal motion about the additional pivot axis; and a bearing affixed to the base and receiving an end of the positioner for longitudinal sliding motion and pivotal motion therein.

Abstract: A cannon barrel assembly has a barrel member centered on and extending along a barrel axis, a barrel tube member generally coaxially surrounding the barrel and having a pair of axially opposite tube muzzle and breech ends, and respective muzzle and breech bearings at the tube ends axially displaceably supporting the barrel member therein. At least one of the bearings comprises two lower and one upper segmental slide elements generally angularly equispaced about the axis and radially set in one of the members against axial displacement therein. The two lower elements are also set in the one member against radial displacement therein while the upper element is limitedly radially displaceable in the one member. Springs braced between the one member and the upper slide element urge same radially against the other member in surface contact therewith and thereby urge the two lower slide elements in surface contact against the other member also.