an autoloader , affixed to a large caliber gun for movement therewith in azimuth and elevation , includes a rammer mounted by a parallel arm linkage mechanism for controlled movement between a lower loading position and an elevated ramming position . while in the loading position , ammunition rounds are singularly released from an ammunition clip to roll by gravity onto a rammer tray for transport to the ramming position . a chain driven ramming pawl then drives the round into the gun breech . a side flap automatically opens to admit a round loaded into the tray and then closes to confine the round on the tray during transport .