8-inch/55-caliber gun

The 8-inch/55-caliber gun was the primary armament of United States Navy heavy cruisers and two early aircraft carriers, its name denoting an 8 inch bore and a barrel 55 calibers long, or 440 inches. It served from 1925 to 1975 across World War II, the Korean War, and the Vietnam War, firing a 335 pound armor-piercing shell or a 260 pound high-explosive shell at a muzzle velocity of 2,500 feet per second to a maximum range of 30,050 yards, and it was built in variants including the Mark 9, Mark 12, Mark 14, Mark 15, and Mark 16. It armed more than 40 vessels, including the aircraft carriers USS Lexington and USS Saratoga and heavy cruisers from the Pensacola through Des Moines classes. This description is adapted from Wikipedia contributors under CC BY-SA 4.0; changes were made. https://creativecommons.org/licenses/by-sa/4.0/