I am surprised that RIA got the caliber wrong---they handle enough guns to know better. The markings are right there in plain sight: "CORDITE 40 - 270 MAX" = 40 grains cordite behind a 270 grain bullet. They compound the error by calling it suitable for the Big Five, and a favorite of John Taylor---on the contrary, Taylor was a fan of the .375 Magnum cartridge, not the .375 Express 2 1/2" (which he disliked).

Nevertheless, great rifle and story!