The Lefaucheux M1858 was a pinfire double action revolver that served as France's primary service revolver from 1858 to 1865. The Lefaucheux was also the first service revolver to use metallic cartridges by any national government.
The Lefaucheux M1858 was of a fairly basic design, with an open frame and a modified percussion lock system. The percussion lock system itself was modified to allow the Lefaucheux to use pinfire cartridges, with the hammer modified to better strike the cartridge. The Lefaucheux also had a basic double action system, and was one of the earliest examples of a true double action system (following the Beaumont-Adams Revolver).
Cartridges were loaded via a hinged gate located at the rear of the cylinder. When open, the gate allowed acess to the the 1st chamber on the right-hand side of the hammer and allowed the user to load each chamber one at a time. The gate would then be closed before firing (although the Lefaucheux would still fire with it open). An extractor system was also featured on the Lefaucheux, which had an ejector rod that ran along the barrel and pushed cartridges out of the gate.
The Lefaucheux M1858 was chambered to accept a 12in diameter bullet, fired from a metallic cartridge. This cartridge was specifically designed for the Lefaucheux with a pinfire primer and blackpowder charge, while the large calibre better matched the other firearms of the era.
The Lefaucheux M1858 was never adopted by the French Army, the French Navy instead adopting it as their primary service revolver in 1858. The French Cavalry would also use the Lefaucheux during their deployment to Mexico in 1862, while other Lefaucheuxs would be sold to various nations such as Switzerland, Spain, Sweden, Italy, Norway and Russia as well as both sides of the American Civil War.
During the American Civil War 12,000 Lefaucheuxs were purchased for use by the Union forces, which were largely issued to cavalry units. Soon, however, the Lefaucheux began to be replaced as Colt and Remington increased their production to quickly supply both sides. The Lefaucheux faced competition from various revolvers of the era, particularly the Beaumont-Adams Revolver (the first true double action revolver) and the Remington 1858.
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