Why the Hawkins-class 7.5-inch gun disappointed

Was the County-class 8-inch gun a clean-sheet replacement for the Hawkins-class 7.5-inch weapon?

Not entirely, but its breech and recoil lineage owed more to six-inch gun development because the 7.5-inch design failed to deliver its expected sweet spot.

The Hawkins-class 7.5-inch weapon disappointed because the intended sweet spot between lighter and heavier cruiser guns did not materialize. The later County-class 8-inch gun was not simply an enlarged version of that weapon. Its breech and recoil mechanisms drew more heavily on six-inch development, carrying existing engineering into the new calibre. The result was neither wholly clean-sheet nor a straightforward 7.5-inch lineage.