Which part of the firearm loads, fires, and ejects shells or cartridges?

• A. Action
• B. Chamber
• C. Barrel
• D. Stock

Answer: (A)

The action is the mechanism that loads, fires, and ejects shells or cartridges. It coordinates feeding a cartridge from the magazine into the chamber, firing the round, and then extracting and pushing the spent case out of the firearm. Different designs handle this cycling in their own ways—bolt-action requires manual operation to chamber and eject, while lever-action, pump, and semi-automatic designs use their respective systems to cycle automatically or with minimal manual input. The chamber is the space that holds the cartridge before ignition, the barrel guides the projectile once fired, and the stock provides stability and grip. So the action is the part that performs the full cycle of loading a new round, firing it, and ejecting the spent case.