A round of ammunition, or a loaded cartridge, consists of a projectile (bullet), a case, powder, and a primer.

Cartridge Case (Click here to order) - These components of the round of ammunition have been called: rounds, cases, cartridges, brass, empties, shells, reloads, reloading brass, spent cases or brass cases. Regardless of the name, Starline manufactures these components. The case has a head on one end that houses the primer and seals the back of the chamber. The flash hole is the hole connecting the primer pocket to the inside of the case. This head can be of several different designs such as belted, rimless, semi-rimmed, rimmed, and rebated (meaning the diameter of the rim is smaller than that of the body). Besides sealing the back of the chamber, the head of the case is used to extract the case from the chamber. There are three sizes of primer pockets that Starline uses; small rifle/pistol, large pistol, and large rifle. The small rifle and small pistol use the same diameter and depth primer pocket. The large rifle pocket is slightly deeper than the large pistol pocket. The body of the case will be one of three styles; straight, tapered or bottlenecked. The bottleneck cases will have a shoulder that steps down to a smaller diameter, while the tapered case will have a slight taper to achieve proper diameter. Straight wall cases are uniform diameter all the way up the body. The inside of the case will be of uniform thickness from the case mouth down to just past where the base of the bullet will seat. It will then become gradually thicker toward the bottom ending in a radius. The area of material between the bottom of the primer pocket and the bottom of this radius is called the web. Starline produces unprimed brass for the purpose of reloading ammo. (Click here to order)

Anatomy of Ammo | Cartridge Case | The Three Ps | When a Firearm is Fired