Comments by "Frank DeMaris" (@kemarisite) on "The Drydock - Episode 167" video.

It's important to keep in mind the weight of the shells in comparing the various 15" guns. The French and Italian guns fired 884 kg shells, while Bismark's were about 10% lighter at 800 kg. While lighter shells will have a greater velocity at the muzzle, it will also tend to lose velocity more quickly. While Bismark's shells are only about 30 m/s slower than the Italian shells at the muzzle, that has increased to 50 m/s at 20,000 meters. That combination of higher velocity and greater weight for the Italian shells translates to a difference of 3-4 inches of expected armor penetration at that kind of practical battle range.
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@tommeakin1732 at 10 kg the bursting charge is on the small side, but I dont think we can call it "tiny" unless we're using the same word to describe all US bursting charges. The 14" guns of the USN had almost identical 10 kg bursting charges, albeit explosive D rather than TNT, and while the British 15"/42 had an 18 kg bursting charge the US 16" Mark 8 also had an 18 kg bursting charge. Theoretical rate of fire is not a particularly useful basis of comparison because, in practice, these guns rarely fire more than about one round per gun per minute. Bismark did almost exactly that at Denmark Strait, with half-salvos for ranging about every 30 seconds at first. Similarly, West Virginia at Surigao Strait opened fire at 0352 and ceased fired at 0402, having fired 91 rounds for a rate of 1.14 rounds per gun per minute. Even dropping out the last two half-salvos, she fired 86 rounds over 8 minutes 14 seconds, a rate of 1.3 rounds per gun per minute. It really just isn't practical to take advantage of the theoretical rate of fire without either ignoring the issue of correction (West Virginia had great radar and was on target for the entire engagement) or getting so close that the correction can be made by the time the guns are reloaded, i.e., down around 15,000 yards. As for the lack of an HE shell, navweaps says the French didn't develop an HE shell for their 15" guns until 1949.
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@tgsachris there are actually two considerations here, whether the shock of hitting the wooden hull is enough to trigger the fuze, and whether a triggered fuze will set off the shell within the ship. HMS Victory is only about half as wide as armored warships got to be, 51 ft vs just over 100 ft for the Panama Canal. Even if the outer planking triggered the fuze, it is still has a delay of, say, 0.1 seconds (it varied on design, from several hundredths to a few tenths of a second). The shell might pass completely through and burst tens of feet away on the other side, making more holes in it but not blowing it apart.
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