Why HMS Dreadnought used ready twelve-inch guns

Why choose twelve-inch guns when larger weapons could hit harder?

The twelve-inch system was ready immediately, and Fisher prioritized completing the revolutionary ship first over waiting for a more powerful but slower design programme.

The expected firing rates of twelve-inch and 13.5-inch guns were nearly identical, while the larger shell hit harder. The twelve-inch system had one decisive advantage: guns and turrets were ready because of the Lord Nelson class. Dreadnought was therefore a conservative great leap forward. Larger guns, triple turrets, superfiring arrangements, and a 24-knot speed were all conceivable, but combining them would have delayed construction. Fisher later claimed he had not realized that superfiring was possible, even though naval constructors and architects had told him it could be done. Had Dante Alighieri appeared first, the Royal Navy might have had to redesign in response. Fisher's choice turns on the value of completing the revolutionary ship before any rival.