Is the 9-mm firearm classified as automatic or semi-automatic?

The classification of a 9-mm firearm as semi-automatic is based on the operation of the firearm itself. In a semi-automatic firearm, a single round is fired with each pull of the trigger, and the firearm automatically chambers the next round from the magazine after each shot. This allows for rapid follow-up shots while still requiring the shooter to pull the trigger for each individual round.

Many common handguns using the 9-mm caliber, such as the Glock 19 or the Beretta 92, function in this manner and are designed for both accuracy and ease of use. This characteristic is what distinguishes a semi-automatic from fully automatic firearms, which continue to fire as long as the trigger is held down, or manual types where each round must be cycled manually, such as bolt-action rifles or revolvers. Thus, the classification of 9-mm firearms as semi-automatic reflects their operational features and common usage among civilian and military shooters.