Britain's real 18-inch gun programme supplies the starting point for the hypothetical development. Work on the 45-calibre weapon for N3 shows that the larger calibre was an actual design concern. The proposed Agincourt combines six 18-inch guns with 28 knots, while a subsequent Hood could also have adopted 18-inch armament. These are counterfactual designs. Larger weapons would change armour requirements and require a stronger hull to withstand the forces of firing.
Notable Point · 2:56:13-2:58:37
How 18-inch guns would change Agincourt and Hood
Real British gun development underlies hypothetical 18-inch Agincourt and Hood designs with different structural demands.