(3) Loading Operations in Turret pos sible rate of fire depends upon the rapidity with which successive rounds can be loaded. The loading cycle for a turret gun involves the following events : (a) The recoil and counter-recoil of the gun.
(b) Opening the breech and ejecting the fired tube (primer).
(c) Bringing the gun to the loading position which is a fixed angle varying in different turrets from 4° to i o° of elevation. In some turrets, such as that shown in the illustration, loading can be performed at any elevation through a loading arm at the rear end of the slide, which is designed for the automatic attachment of the ammunition cage, which then moves up and down as the gun is depressed or elevated. This enables the loading operation to proceed without the gun being brought to a fixed position. The loading arm carries on its extreme end a chain rammer for ramming home the projectile and charge, hence this operation also is independent of the angle of the elevation.
(d) Bringing the ammunition cage with projectile and charge from the waiting position in the chamber to the loading position or loading arm. (Bringing the ammunition from the shell room
and magazine by the main trunk and transferring it to the load ing cage is an operation which can be performed at any time and is not dependent on the working of the gun.) (e) Ramming home the projectile and charge. In some mount ings, where fixed loading is carried out, telescopic rammers are used and the charge is automatically picked up by the rammer behind the projectile and carried into the gun chamber in the same ramming operation with the projectile.
(f) The withdrawal of the rammer and cage.
(g) Closing the breech with a new tube in position.
When the loading is completed a hand-operated switch is put over. This break in the firing circuit is introduced to ensure safety from firing during the loading operations. The gun is now ready for firing, and this can be performed by completing the firing circuit by pressing a key either in a sighting position in the turret or in the director tower, according to which position is connected up.