. . "yes"@en . . . . . "Mk I, Mk II"@en . "The BL 4.7 inch 45 calibres gun (actually a metric 120 mm gun) was a British medium-velocity naval gun introduced in 1918 for destroyers, to counter a new generation of heavily-armed destroyers Germany was believed to be developing."@en . "1918"^^ . "BL 4.7 inch /45 naval gun"@en . . "bore"@en . . "yes"@en . . . . "yes"@en . "BL 4.7 inch 45 calibre naval gun"@en . . "1917"^^ . . . . . "1930.0"^^ . "The BL 4.7 inch 45 calibres gun (actually a metric 120 mm gun) was a British medium-velocity naval gun introduced in 1918 for destroyers, to counter a new generation of heavily-armed destroyers Germany was believed to be developing."@en . . .