The comment notes that Fuso needed considerable length to accommodate six twin 14-inch turrets, suggesting that the mounting choice was deliberate. A gun described as 40 calibres long measures forty times its bore diameter. A 40-calibre 12-inch gun is about forty feet long, while a 14-inch weapon of the same relative length adds roughly six feet eight inches. The difference grows further with 45- or 50-calibre weapons, so changing calibre affects turret and hull geometry as well as shell diameter.
Notable Point · 32:00-33:23
Why larger-calibre guns rapidly lengthen a battleship layout
A Fuso-class example shows how the calibre-length convention makes a 14-inch gun substantially longer than a 12-inch weapon and complicates multi-turret hull arrangements.