The Royal Navy wanted a destroyer gun system powerful enough for surface and anti-aircraft work. A destroyer mounting with sufficient firepower was not ready, so HMS Savage tested a spare turret from HMS Illustrious. The capital-ship-derived mounting penetrated two decks and consumed internal volume that the hull had not originally been arranged to provide. Those constraints help explain why the Battle class carried only two twin main turrets and concentrated both forward.
Chapter · 19:26-21:08
Deck-penetrating turrets shaped the Battle-class layout
The Battle class needed powerful dual-purpose guns before a suitable destroyer mounting existed, so capital-ship-derived turrets reached deep into the hull and forced the main battery forward.