As far as auto loaders in the WW2 era for large cannon . ie 3 inch and up , what you find is very complicated autoloaders designed for aircraft applications with the gun not traversing or elevating . In a large calibre Naval gun the rate of fire is both theoretical and practical . IE the gun can return to loading position after firing in X seconds . then it takes Y seconds to set a fuse and load a shell . This creates a rate of fire the gunners try and achieve and in practice do not maintain the rate of fire for very long due to fatigue . If however you design an autoloader on the mount that sets the fuse , rams it immediately then fires and begins the cycle again .
One of the more interesting systems I remember reading about was one where the shells where placed on the loading tray and as the rammer engaged it would push to a certain position and rollers would set the fuse then the ramming would complete and shell fired . I think a similar system of loading (not the fuse setting part )was on the Soviet era 100 mm AA gun that was exported everywhere . This involved a tray that elevated with the gun upon which shells could be loaded by hand then gravity and some recoil operated system moved them sideways onto loading tray .
One of the more interesting systems I remember reading about was one where the shells where placed on the loading tray and as the rammer engaged it would push to a certain position and rollers would set the fuse then the ramming would complete and shell fired . I think a similar system of loading (not the fuse setting part )was on the Soviet era 100 mm AA gun that was exported everywhere . This involved a tray that elevated with the gun upon which shells could be loaded by hand then gravity and some recoil operated system moved them sideways onto loading tray .