What if building some of these in 1/700 styrene?

[Joe C-P]

The Montana hull was more like that of the North Carolinas than the Iowas. The 5" twins were arranged differently, and were 54 caliber. Bob Dulin and Bill Garzke's book on US Battleships is an excellent and very detailed resource.

As pyro-maniac discussed, even the Yamato's 18" guns caused self-inflicted damage, and firing them essentially required all crew to be under cover. 20" would have caused much more damage, more whipping of the barrels and thus less accuracy, and reduced effectiveness as 6 barrels of much bigger shells couldn't have been fired as often.