Abstract: A conveyor for large caliber ammunition includes upper and lower chains mounted within a magazine to run in a compact serpentine path. The lower chain includes platform links on which ammunition rounds (projectiles and propellant canisters) rest in upright orientations. Resiliently backed ball casters, affixed to the upper and lower chains, run in magazine guide tracks and roll on the track bottom surface to provide smooth and efficient conveyor operation. Retainers cradle the ammunition rounds to maintain their upright stand on the conveyor and to ensure that they are safely propelled through the turns in the serpentine conveyor path.