Which component of a cartridge produces a large volume of gas when ignited?

The powder in a cartridge is the component responsible for producing a large volume of gas when ignited. When the primer is struck and ignited, it ignites the powder, which undergoes a rapid chemical reaction that generates a significant amount of hot gas. This gas expands quickly, creating high pressure within the cartridge case, which then propels the bullet out of the barrel at high velocity.

The other components play different roles in the functioning of a cartridge. The bullet is the projectile that is fired from the cartridge, while the wad serves as a separator between the powder and the bullet in certain shotgun cartridges. The primer is a small explosive component that initiates the ignition of the gunpowder but does not contribute significantly to the volume of gas produced. Understanding these roles is crucial when studying the mechanics of ammunition and firearms.