Comments by "Old Guy Gaming Network" (@CRAZYHORSE19682003) on "Battleship Guns of WW2 - A series of tubes" video.

The Scharnhorst was designed to have the same guns as the Bismarck class. However technical issues with the design of the turrets cause a delay. The 11 inch guns were a placeholder and were never intended to be the main battery.
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@Melvorgazh The Gneisenau actually went into the yards to be regunned but allied bombing raids damaged her so much that the upgrade was canceled and all her armament was taken off and and she was sunk as a block ship in Gdynia Poland. As far as the technical issues I don't remember reading anything specific other than the turret was a brand new design and was not ready and the delays would have caused a delay in Scharnhorst and Gneisenau entering service so it was decided to arm them with the 11 inch triple turrets as a stop gap measure.
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Wouldn't have mattered, by the time the KGV's got close enough to where their guns could penetrate Iowa's armor they would have been blown out of the water by the Iowa's 2700 pound AP shells.
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@aw34565 Except the KGV did not have thicker effective armor. The KGV had a 14.7 inch armor belt that was vertical. The Iowa had an internal angled armor belt. When you add the 1.5 inch or 38mm of STS hull plating the 12.1 inch (307 mm) internal angled armor belt and the .875 inch (22.2 mm) STS backing plate the belt was mounted to it gave the Iowa's the equivalent of 17.3 inches(439 mm) of vertical armor. The Iowa's and South Dakoda's were the best protected battleships not named Yamato. I will also mention the barbettes and turret faces of the KGV were weak at 12.75 inches(324 mm) compared to the Iowa's turret faces of 19.5-inch (495 mm) and barbettes of 17.3 inches (439 mm). A fight between a KGV and an Iowa or South Dakoda class battleship would be a short one sided ugly encounter with the American ships absolutely wrecking the KGV's.
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