Comments by "Steve Valley" (@stevevalley7835) on "The Drydock - Episode 200 (Part 1)" video.

  1. wrt to Dr D M Platt's question about replacing guns, expanding a bit on gun refurbishment, since he mentions whether a gun has a liner or not: To replace the liner the gun was placed in a pit, and the outside tube heated, while cool water was flushed through the bore to cool the liner, with the difference in thermal expansion between the cool liner and hot tube hopefully loosening the liner so it could be pressed out. Initially, the USN made liners with a uniform outside diameter, but then realized if the liner's outside diameter had a slight taper the chances of successfully pressing the liner out were improved. If the liner refused to be pressed out, then the procedure is the same as refurbishing a gun that was not originally made with a liner: the inside of the gun would need to be bored out to entirely remove the stuck liner, or to prepare a gun to have a liner fitted for the first time. Boring out a gun would take several weeks. I may have a more specific number in my notes somewhere, but I recall reading that the boring time was a matter of 3-4 days, for each cut. I just found a piece on youtube by Ryan, the curator of Battleship New Jersey, talking about 16" gun construction and maintenance. He says the refurbishment process, if all goes smoothly, took about 2 months.
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  2.  @timothyschmidt9566  you made me look it up. :) The Des Moines class used Mk 16 guns, which Navweaps says were apparently the first mark that used a "loose liner", secured by a liner locking ring, rather than the usual shrink fit. That would explain how the liners could be removed with less temperature differential and force to break the liner loose than was the case with earlier shrink fit liners. I learned something tonight. Thanks!
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  3.  @Rdeboer  that question came up in a FB group, specifically, why did Warspite retain most of her 6" secondaries in her rebuild, as the twin 4"/45s that were installed were capable of performing as dual purpose guns. Removing all the 6" and replacing them with twin 4"/45s would triple her heavy AA armament, potentially resulting in the ship taking less damage from aircraft. A question along the same lines came up, if Bismark had gone all in on the 105mm gun, instead of dividing deck space between the 105s and 150s, that would greatly have improved the probability of splashing a particular Swordfish. Seems that the roadblock to going all in on 4"-5" DP secondaries was a consensus that heavier secondary guns were needed for dealing with attacking destroyers. The one dissenter to that consensus appears to be Jackie Fisher. Jackie held that a quick firing 4" was perfectly fine for dealing with light surface targets. The two classes Jackie had a hand in designing during WWI, the Renowns and Courageouses, had low angle 4" secondaries, while the QEs, Revenges and Nelsons all had 6". To directly answer your question, yes, the adoption of DP guns greatly increased AA firepower. Had more navies abandoned the concept of dedicated, heavy, low angle, secondary armament, more deck space would have been available for armament that could perform in the AA role, as well as anti-surface.
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  4.  @jbepsilon  I think the issue was that no country could have a ship substantially more powerful than what other countries had. The objective was also to limit the cost of new ships. So, BBs were set at 35,000 tons/16" guns, because, except for Hood, those were the parameters of the ships just then coming into service: the Colorados and Nagatos.
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  5.  @vixtontitano2394  It seems that political influence played a part. The ship that history knows as the New Mexico was laid down as California. She was renamed New Mexico in March of 1916, due to pressure from A A Jones, First Assistant Secretary of the Interior, who was from New Mexico. The California Congressional delegation was fine with that, as they pressured the Navy to build a BB at Mare Island, named California. If I think of it, I might start digging through the archives to see if BB 44 had always been planned to be built at Mare Island, or if it was reassigned to placate the California Congressional delegation.
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  6.  @vixtontitano2394  I started looking through newspapers from late 1915 when the bids for BB 43 and 44 were opened. The two low bids, under $7M were from the New York and Philadelphia Navy yards, while Mare Island bid $7.4M. Neither Philadelphia or Mare Island were presently equipped to build battleships. Mare's bid included the money for needed improvements, Philadelphia's did not. Ballpark estimates for improvements in Philadelphia ran from $200,000 to $400,000, which, on top of the construction bid of $6.774M was still less than Mare Island's. SecNav Daniels asked Congress for $175,000 to extend the slipway and dredge the channel in Philadelphia to allow battleships to be built, on December 6. Then Daniels met with President Wilson. Suddenly, the estimate for improvements in Philadelphia jumped to $1M on December 10th, which made Mare Island cheaper. At that time, BB44. the one to be built in Mare Island was unnamed. Then Assistant Secretary of the Interior Jones was given the credit for changing the name of the ship building in New York from California to New Mexico in early 16, freeing the name California for BB44. Thanks for asking that question. Newspaper reports of this sequence of events made for fascinating reading.
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