Is the bullet casing copper or steel now? During World War II, the bullets were basically copper-clad bullets, so I heard that the bullets in China were steel-clad bullets.

There are many kinds of shell materials, most of which are brass. However, due to the lack of copper resources and limited military expenditure in China, there are few brass casings in China, mostly pistol casings, such as 92-type 9MM bullet casings. A large number of casings made in China are copper-clad steel, that is, the casings of the main steel structure are covered with a layer of copper back armor, such as the casings of 7.62MM ammunition used in Type 56 assault rifles and rifles, and the casings of 8 1 rifles. In recent years, due to the improvement of military processing technology in China, ammunition coated with steel shell has been produced, that is, a thick layer of paint is brushed on the main body of the steel shell, such as the 5.8MM bullet used by Type 95 gun family. Copper-clad steel and painted steel shell can save a lot of expensive copper resources and have good deformation resistance, but they have serious wear on firearms. Let's talk about why copper plating and painting are needed to protect the cavity and reduce wear. Because copper is soft, wear is small and steel is hard, measures must be taken to reduce friction.