How Hawkins shaped treaty cruiser limits

Why did the Royal Navy move from Hawkins-style single 7.5-inch guns to twin 8-inch cruiser turrets?

The treaty made 8 inches the practical maximum, while existing twin-turret experience and competing survivability considerations supplied a workable design path.

The Washington limits effectively rounded the Hawkins class's displacement and 7.5-inch armament into the 10,000-ton, 8-inch treaty-cruiser formula. The treaty therefore made the 8-inch gun the practical maximum even though Britain had used other cruiser calibers. Existing twin-turret work on HMS Enterprise offered a usable development path. Designers still debated three larger turrets against four smaller ones because losing one of three removed a greater share of the battery. Treaty geometry, available engineering, and battle-damage tolerance all shaped the resulting cruiser rather than caliber choice alone.