The damaged 1905 dreadnoughts have enough armour to trigger armour-piercing shells, though that does not automatically make them the best ammunition. Against the earlier pre-dreadnoughts, an all-high-explosive load might have destroyed targets faster. By this stage the ship has already consumed its high-explosive 5.3-inch ammunition and must continue with armour-piercing rounds. Magazine endurance depends on shell count and on carrying the right ammunition mix for the expected targets.
Notable Point · 1:18:37-1:19:31
Shell choice changes the ammunition problem
The older ships' limited armour makes high explosive attractive, but the modern ship exhausts that part of its secondary ammunition first.