The term "express" as applied to rifles originated with James Purdey's "Express Train" rifle, a caplock muzzle-loader, introduced in the 1850s.

The .450 3 1/4" NE, introduced in 1898, is commonly considered the first nitro express. However, some references say the .450/.400 3" Nitro Express was introduced in 1896. Since this cartridge was only introduced after pressure-related extraction problems with the full nitro loadings of the .450/.400 3 1/4" NE, it is obvious that the 3 1/4" predated the 3". However, I don't believe the 1896 date for the 3".
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