The 130mm/55 B7 Pattern 1913 naval gun was a 5.1-inch naval gun used predominantly on ships of the Imperial Russian Navy and later by the Soviet Navy. It was manufactured mainly by the Obukhov State Plant (OSP) in St. Petersburg, as well as under licence by Vickers Limited in Great Britain. The gun was used as medium artillery on several Russian dreadnoughts and as main artillery on cruisers, as well as coastal artillery. It was succeeded by the 130 mm/50 B13 Pattern 1936 naval gun, which became the standard destroyer gun of the Soviet Navy during World War II.