Comments by "Todd Webb" (@toddwebb7521) on "World's Worst Warships - Book Review with Drach (Part 2 of 2)" video.

http://www.navweaps.com/index_nathan/Penetration_Britain.php The 15"/ 42 Cal will pretty much penetrate the thicknesses of armour actually produced out to the ranges you can actually expect to hit to, obviously a 16" is going to have a bigger bursting charge and be able to penetrate more armour at a longer range if your enemies started building heavier armoured paper battleships that didn't get made irl like H series and super yamatos. 14" definitely doesn't compare as well with either may have to get like 16km to penetrate enemies that a 15 would penetrate at over 20km.
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http://www.navweaps.com/index_nathan/Penetration_Britain.php 15"/42 could pretty much penetrate anything actually built out to the range you can actually hit it, but a 16 has more explosive when it gets there and can penetrate a little more if your enemies ever built something more heavily armoured like the paper battleships 14" definitely don't compare well, they need to be closer to penetrate some of the heavier stuff that existed and that's not to mention if paper stuff got built.
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