What is the shell made of?

Shell material: Generally, the shell is made of copper, because copper can conduct heat quickly, expand rapidly when it is launched, fill the space in the bore, and shrink rapidly after it is launched, which is convenient for shell extraction. Now many countries are developing aluminum shells and plastic shells, which are much lower in price and weight than copper and steel warheads.

Waste shells can also be reused.

Wu Zengdong is the third generation descendant of Li Jinhe Knife Shop in Jinmen, Taiwan Province. His grandfather made a living by striking iron, studied in Xiamen, Fujian, and 1937 founded the knife shop. Over the past 60 years, the knife shop has developed into "Li Jinhe Industrial Co., Ltd.", and Wu's knife shop has made the world-famous "Golden Gate Steel Knife" from discarded shells.