The basic parts of ammunition are four key components: the casing, the primer, the powder (or propellant), and the projectile (or bullet).
The Casing
The casing, often called the cartridge case or brass, is the outer container that holds all the other parts together. It is usually made of brass, steel, aluminum, or sometimes plastic (in shotgun shells). The casing holds the primer, powder, and projectile, and its shape ensures proper fitting and function in the firearm chamber.
The Primer
The primer is a small metal cup containing a chemical compound that ignites when struck by the firing pin. The ignition fire travels through a flash hole to ignite the powder inside the casing. Primers can be rimfire or centerfire depending on their location on the casing.
The Powder (Propellant)
Powder, or propellant, is the substance inside the casing that burns rapidly when ignited by the primer. This combustion generates high-pressure gases that propel the projectile out of the barrel. Smokeless powder is most commonly used today, while black powder is historical and still used in replicas.
The Projectile (Bullet)
The projectile, commonly called the bullet, is the part that leaves the barrel and hits the target. Bullets can vary in shape, size, and material depending on their purpose (e.g., hunting, self-defense, target shooting).
In shotgun shells, there is an additional component called the wad, which separates the powder from the shot and helps control the shot pattern.
Thus, the four essential parts of ammunition are the casing, primer, powder, and projectile.
