A treaty might round the category's calibre limit to 10 inches, but the Royal Navy's practical design choice remains 9.2 inches. The 10-inch weapon falls into a slower firing-rate band without offering the full value of a capital-ship gun. The smaller weapon permits larger batteries, more armour, or both within an 18,000- to 20,000-ton cruiser because its guns, shells, and handling machinery are lighter. A nominal 10-inch ceiling would therefore give other navies room to experiment while leaving Britain with a well-balanced and already familiar calibre.
Notable Point · 2:02:50-2:04:09
Why 9.2-inch guns remain the preferred battery
The British would likely retain 9.2-inch guns because a 10-inch weapon adds weight and sacrifices rate of fire without enough compensating value.