Comments by "Steve Valley" (@stevevalley7835) on "The Drydock - Episode 201" video.

  1. wrt the question about RN secondaries, seems the reversion to 4" on the Renowns and Courageouses was due to Jackie Fisher's involvement in the design of those classes, as he believed that a quick firing 4" was a better choice than a casemate mounted 6". As soon as Fisher was no longer involved in designs, the RN reverted to a heavier secondary on the Nelsons. I did a bit of comparison between the USN 5"/51 and the dual 4"/50 that was experimented with on a few USN destroyers. The guns had the same rate of fire, but the 4" was a twin. The 5" had slightly better armor penetration, but the DDs the secondaries were intended to fend off were not armored. They had virtually the same range. The single 5"/51 and twin 4"/50s, guns plus mount, weight virtually the same. Creating a hypothetical USN DP 4" mount, cutting the 4"/50 down to 45 caliber to reduce the moment of inertia, and mounting them on a copy of the RN DP mount used with the British 4"/45 Mk 16 in the mid 30s, would give a twin mount that weighed less than the combination of a 5"/51 and a 5"/25 that modernized USN standards were equipped with in the 1930s, while providing twice as many guns in each role, while leaving the 01 deck clear, for installation of additional light AA.
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