Comments by "" (@RedXlV) on "The Drydock - Episode 185" video.

Especially since she was not just the last survivor of the Kaiserliche Marine, but also the last surviving battlecruiser.
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I wasn't aware that British BL 18"/40 Mk I was relined as a 16"/45 testbed. I was however aware that the US Navy did the same thing with the single prototype barrel of the 18"/48 Mark 1. When the Washington Naval Treaty put an end to any notion of 18" guns on a warship, they relined it to create the 16"/56 Mark 4, to test out the performance of a very high velocity gun. In 1938, when treaty restrictions ceased to be relevant, the threaded tip that held the 16" lining in place was cut off and it became the 18"/47 Mark A, which tested a super-heavy 18" AP shell, weighing in at a whopping 3,850 pounds. (Though honestly I'm slightly disappointed they didn't test out a full 2-ton shell, because that would've been hilarious.)
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@joshwilliams4344 Not at the time the 18"/48 gun was made. Though the reason they converted it back to an 18" is that there was at least consideration of using it for what would ultimately become the Montana-class. As such it was considered worthwhile to test out a super-heavy 18" shell. Though by the time they started actually drawing up Montana designs, they'd settled on sticking with the 16"/50.
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