Autoloader
The T-72's autoloader design is not based on the faster, but more complicated autoloader in the USSR's domestic-use-only T-64 tank series (the T-72's is horizontally auto-fed, the T-64's uses vertical actuators). The autoloader must crank the gun up three degrees above the horizontal in order to depress the breech end of the gun and line it up with the new shell. While autoloading, the gunner can still aim because he has a vertically independent sight. With a laser rangefinder and a ballistic computer, final aiming takes at least another three to five seconds, but aiming is pipelined into the last steps of auto-loading so it proceeds concurrently. The average rate of fire for this type of carousel automatic loader is quoted to be 8 rounds per minute. The use of the autoloader allows the elimination of the extra loader crewmember, decreasing the size of the tank.
Read more about this topic: T-72, Design Characteristics