Cases are made of brass, steel, or aluminum. Brass is the most common. Shotgun shells are often made with a polypropylene

Many handgun and rifle bullets used for competition shooting are cost using conventional costing methods. The molten lead is poured into the bullet mold cavity, cooled quickly, and then extracted from the mold. The typical brass case is formed from annealed sheet by drawing with a multiple punch and die set. [/align][/align]plastic case attached to a metal base. A few handgun cartridge cases have been made of plastic, but have not received wide acceptance.


Case Design &
Manufacture
Nearly all small arms ammunition cases are of brass alloy. Some use aluminum, steel, or plastic, but the brass case is most popular and easiest to manufacture.
The design of the case is determined by the firearm in which the ammunition is used. The typical brass case is formed from annealed sheet by drawing with a multiple punch and die set. The first stage of the multiple die set forms the metal, the second stretches the metal deeper, the third forms the rim, and so on. Each step stretches the metal slightly farther until the final stage produces an accurately formed case. The cases are trimmed to length and the primer hole is punched. Heat treating and stress relieving are performed to selected types of cases to improve durability.

This is accomplished in large batch ovens, where baskets of cases are heated with enough temperature to gently soften the metal without distorting it. When cooled, the metal is "relaxed" and better able to take the punishment of firing. Some handgun caliber cases are nickel plated for durability in reloading, corrosion resistance, and for appearance. Each case is stamped with information such as caliber, manufacturer, munitions codes, and year of manufacture.