What is the method of operation for the 9-mm M9?

The method of operation for the 9-mm M9 is classified as short-recoil. In this system, the energy generated from the recoil of the fired cartridge is used to cycle the action of the handgun. When a round is fired, the barrel and slide move together for a brief distance, allowing the bullet to exit the muzzle before the two separate. This separation is essential, as it allows the slide to move rearward, eject the spent cartridge case, and chamber a fresh round from the magazine.

Utilizing the short-recoil operation provides several advantages, such as reducing the amount of energy required to operate the action and improving the overall reliability and durability of the firearm. The mechanism is efficient and ensures quick follow-up shots, making it a popular choice in military and law enforcement handguns like the M9.

The other methods of operation listed have distinct characteristics that set them apart. Blowback operates by using the weight of the bolt and spring tension to manage the cycle without needing a locking mechanism, which is not applicable to the M9. Gas-operated systems typically utilize gas from fired cartridges to cycle the action, commonly found in rifles and some automatic pistols, but are not the design for the M9. Pump-action relies on manually operating