A medium-caliber ammunition supply device for a turret mounted on an armored vehicle includes: at least one circular turntable, placed at the rear of the turret, for positioning medium-caliber ammunition in a strip or chain, vertically and along a spiral path; and structural elements for guided and pulled conveyance of at least one strip or chain of medium-caliber ammunition. The structural elements include at least a conveyor and a ratchet box. The structural elements successively include a first conveyor, a first ratchet box, a second conveyor, and a second ratchet box. The at least one circular turntable and the structural elements all are covered with a sheet-metal protection on their side faces and/or on an upper part or roof. The sheet metal protection has mobile hatches mounted in a rotating or pivoting manner, allowing partial or complete and ergonomic (re)loading and/or unloading of the at least one circular turntable.