Eighteen Inch Guns The Yamato-class battleships had primary armaments consisting of three 3-gun turrets mounting 46 cm (18.1 in)/45 caliber Type 94 naval guns – the largest guns ever fitted to a ...

Meet the Yamato-Class Battleships: The largest, most massive battleships to ever exist were the Japanese Yamato-class WWII-era warships which incorporated nine ultra-large 460mm 18.1-inch naval guns.

BAE also has successfully tested the Multi-Service Standard Guided Projectile (MS-SGP), a 5-inch guided projectile designed to be used in land artillery or naval guns.