How does a semi-automatic firearm operate?

A semi-automatic firearm operates by utilizing the energy generated from the fired round to perform several key actions automatically. When a round is fired, the gas pressure forces the slide or bolt to move, ejecting the spent casing and chambering a new round from the magazine. This process allows the shooter to maintain a relatively quick rate of fire without manually reloading each individual round.

This operation is distinct from fully automatic firearms, which continuously fire as long as the trigger is pressed, and from manual mechanisms where a shooter must manually load each round. The efficiency of a semi-automatic action means it achieves a balance between rapid fire capabilities and maintaining control over each shot, as the shooter must still pull the trigger for each round fired.