What component ignites the gunpowder in ammunition?

The primer is the critical component that ignites the gunpowder in ammunition. When the firing pin strikes the primer, it creates a small explosion that ignites the propellant or gunpowder within the cartridge. This ignition is essential for firing the bullet.

The case holds all components of the cartridge together, while the projectile refers to the bullet itself that is expelled when the gun is fired. The wad is typically found in shotgun shells and serves to separate the shot from the powder and help create a seal in the barrel, but it does not ignite the gunpowder. Understanding the function of each component is key to grasping how ammunition works in firearms.