After firing a round the breech plug is swung down and the spent primer case is automatically ejected.  The primerman, standing on a platform below the shelf plate, inspects the mushroom stem hole and inserts a loaded primer.  Due to safety interlocks, the primer cannot be fired until the breech is closed completely.  In the event of a misfire the gun can be reprimed without opening the breech.

Retracting the Rammer and Spanning Tray:

The tray is mechanically attached to the cradle fulcrum by means of the spanning tray control link.  Raise the cradle, and the tray retracts and folds; lower the cradle, and the tray unfolds and extends.  Hand signals are used because of the noise, from the electro-hydraulic drives for instance, although the sound of the firing itself is quite subdued within the turret.  

The breech plug, released by a foot treadle, swings up through spring load and air pressure.  As the plug is rotated by a cam to lock the breech, the operating lever swings up almost to its latch.  To complete the process, the gun captain must step forward and push the lever home, as he is doing here with his left hand.  Note the analog counter on the right recoil cylinder which records the total rounds fired by the gun. 

After sealing the breech, the gun captain steps back and and throws his ready switch.   With its unlocking solenoid, this switch can be moved from the safe position only when the breech is closed.  On one circuit, the switch is connected with the firing keys.  On the other, the switch is arranged with the turret officer's indicator panel.  After the gun has been fired the gun captain turns the switch back to safe, and the weapon is lowered to its 5 degree loading angle.

All of these operations take only 30 seconds with an experienced turret crew.  The variety of steps, keyed precisely into one another, is quite evident from this schematic view of the firing cycle.