This is neat.
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These days we take for granted that a self-contained cartridge has a primer mounted in the center of the cartridge bottom, but there was once several competing systems. In the 1820s, a French gunsmith named Casimir Lefaucheux invented the pinfire system, which featured a priming pin that protruded from the side of the cartridge.
Lefaucheux's original design was for a double-barreled shotgun. A pinfire revolver was patented in England in 1854, though my sources disagree as to whether it was Casimir or his son Eugene who patented the design. In either case, the pinfire revolver was used extensively during the Crimean War and adopted by the French Navy. The example shown to the right is an 18-shot pinfire revolver with twin barrels.
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