Gunmetal, also known as Red Brass in the United States, is a type of bronze - an alloy of copper, tin, and zinc. Proportions vary by source,but 88% copper, 8-10% tin, and 2-4% zinc is an approximation. Originally used chiefly for making guns, it was eventually superseded in this department by steel.

Gunmetal alloys are used to make steam and hydraulic castings, valves, pump parts, steam fittings, gears, bearings, statues, and small objects such as buttons. Modern admiralty gunmetal is composed of 88% copper, 10% tin, and 2% zinc.