Curl:

I believe the ban was 1906, IIRC.

The idea that the .450s were no longer made after the ban is an old wives tale. The .450 3 1/4" especially was quite popular until very late in the game. Double rifles continued to be made for it at least until WWII. Kynoch dropped the .450 No. 2 and the .500/.450 immediately after the war, but continued to load .450 3 1/4" until they shut down in 1973. Late run Cordite for it is still easy to find.
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