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British Cartridges
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.577" Nitro Express
The 577 B.P. Express (B.P.= Black Powder) was introduced in the early 1870's, and  was changed
to  the .577" Nitro Express in the early 1900's when it was loaded with "Cordite" smokeless
powder.
Today this cartridge is loaded with regular smokeless powder as cordite is no longer in production.
It was produced in 3 lengths: 2&3/4", 3" and  3&1/4" lengths).
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