The USS Missouri's main guns were nine formidable 16-inch/50 caliber Mark 7 cannons, housed in three triple turrets, capable of firing 2,700-pound armor-piercing shells over 20 miles with devastating force, using massive powder charges to propel projectiles at high velocity, making them powerful enough to penetrate heavy armor and destroy fortifications. Each gun barrel was enormous, weighing 134 tons and stretching 68 feet long, delivering immense firepower and enabling the ship to engage targe

Battleship Guns: "16 Inch Gun & Turret" 1955 US Navy Training Film for Iowa Class Battleships | Popular Mechanics