Rigby developed the .450 3 1/4" NE.

Much of the conventional wisdom about the history of the British nitros is anecdotal and hard to pin down. For example, the vast majority of references say that the .470 was developed by Lang and introduced in 1907 along with the rest of the .470 group. This information appears to have originated with Taylor. However, it seems to have been Rigby that delivered the first .470 rifle in March, 1900 and it is more likely that they developed the cartridge.
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