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

• A. action
• B. stock
• C. barrel
• D. trigger

Answer: (A)

The action is the part that loads, fires, and ejects shells or cartridges. It handles the cycling of a cartridge by feeding a round from the magazine into the chamber, firing by igniting the primer, and then extracting and ejecting the spent casing. In bolt-, lever-, or slide-action designs, the user or the mechanism moves the bolt or slide to cycle rounds; in semi-automatic systems, the energy from firing drives the action to cycle automatically. The barrel simply guides the bullet after ignition, while the stock provides support and the trigger releases the firing mechanism but does not cycle cartridges by itself.