Comments by "Steve Valley" (@stevevalley7835) on "HMS Orion - Guide 410" video.

  1. Seems so wasteful to scrap ships that were relatively new. But, considering how much the USN spent on it's older ships, converting to oil fuel, adding bulges and deck armor, it was probably the more sensible move. Apparently the Admiralty did not spend much on the Iron Dukes, until they went to the breakers a decade later.
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  2.  @jrd33  quite so, though running costs would have been reduced by putting some ships in reserve. The USN spent a considerable sum modernizing obsolete BBs into ships that were still obsolete. I have seen numbers in the range of $118M, cited by a Senator, in 1930, who was advocating the US not sign First London, and use the money to build new, effective, ships, instead.
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  3.  @willpat3040  I don't understand the physics involved, but I have read that a heavier shell retains it's momentum longer.
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  4.  @willpat3040  You are going by the tables on Navweaps? The muzzle velocities are different. On the Mk 7 gun, the AP is fired at 2500fps, the HC is fired at 2690. On the Mk 6 gun, the AP is fired at only 2300fps, while the HC is fired at 2635fps. The different guns use a different charge. The Mk 6 uses a 535lb charge. The Mk 7 uses a 660lb charge. The tables do show how the lighter Mk 13 shell loses momentum faster than the Mk 8, which weighs 800lbs more. In the Mk 6 gun, the lighter Mk 13 starts out at 2635fps vs only 2300 for the Mk 8. But, 30,000 yards out, the Mk 13 has slowed to 1375, while the heavier Mk 8 is steaming along at 1490.
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  5.  @willpat3040  It is a combination of weight of shell, and muzzle velocity. MV for the 2110lb Mk 3 shell, in a Mk 1 16", is 2600fps, using a 590lb charge. MV for a 2240lb Mk 5 shell, in a Mk 5 gun, is reduced to 2520fps, with a smaller 545lb charge. The 2700lb Mk 8 shell, in a Mk 6 gun, is fired at only 2300fps, using an even smaller 535lb charge. Everyone wants to hit with maximum kinetic energy. The equation is E=M(V squared), so the most efficient way to increase kinetic energy would seem to be to increase velocity, but high velocity guns tended to have issues with dispersion and rapid barrel wear. Then someone noticed that heavier shells retained more velocity at range. Using the tables on Navweaps, the Mk 3 was traveling at 1656fps at 17,300yds,, the Mk 5 travels at 1629 at 20,000yds, and the Mk 5 travels at 1604 at 20,000, nearly the same velocity at impact as a Mk 3, at longer range, in spite of a slower muzzle velocity, and delivering a lot more weight, hence more kinetic energy. Losing a bit of extreme range to obtain the greater kinetic energy at combat range is immaterial, as the chances of hitting anything at more than 30,000 yards are pretty slim. So subsequent marks of 16"/45 guns and AP shells trended to heavier shell, smaller charge, and lower muzzle velocity, for better accuracy, better penetration, and better barrel life.
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  6.  @willpat3040  well, I posted a very detailed comparison of shell weight, muzzle velocity, and shell velocity at range, to make a point about kinetic energy, a few hours ago. But now it has vanished.
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