The M1 is an air-cooled, gas-operated, clip-fed, semi-automatic, shoulder-fired weapon. This means that the air cools the barrel; that the power to cock the rifle and chamber the succeeding round comes from the expanding gas of the round fired previously; that it is loaded by inserting an en-bloc (i.e., it goes into the rifle's action and functions as part of the rifle) metal clip (containing eight rounds) into the receiver; and that the rifle fires one round each time the trigger is pulled.[7]

https://en.wikipedia.org/wiki/M1_Garand