Designed by brothers Charles and Sebre Howard and first patented in 1862, this is a single shot lever action produced by the Whitneyville Armory between 1866 and 1870. It is a really neat compact design that is all contained within a tube. The system was made in rifle, sporting rifle, and shotgun configurations, with a total production of not more than about 1700. The rifle pattern guns, like this one, were chambered for .44 Rimfire. A prototype military configuration example was tested unsuccessfully by the US military in 1867.
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Everybody was looking to create the next great rifle sensation and hopefully obtain large lucrative military contracts. One of the more unusual designs I have ever seen. Someone ought to bring that back as a real production rifle for reenactors. They sould try the same reproduction of the Evans rifles.