Re: Flintlock Riffle
It was once a flintlock, probably a French Model 1829 musket. It was coverted first to percussion c. 1841, then converted again to use a center-fire cartridge, c. 1867. The cartridge conversion uses the French "tabatiere" system; the word means "snuffbox", derived from a fancied resemblance to the snuffbox lid of the era. When the old muskets finally became hopelessly obsolete, they were sold to gun merchants, mainly in Belgium, where hundreds of thousands were converted to shotguns for sale in Africa, South America, and the U.S. Sales in Africa were so common those were lumped with other inexpensive shotguns under the name "Zulu" guns.
They were sold in the U.S. in the 1870's and 1880's for around $4.00 through mail order houses and gun shops.
That does not mean that that gun was not brought from England, but it would have been a lot of trouble for an inexpensive gun. Despite its interesting history, the gun is not very valuable; they usually run around $100-150 as novelties, not much more (allowing for inflation) than the $4 they sold for in the 1880's.