The Palmer carbine holds the distinction of being the first metallic cartridge bolt action firearm ever adopted by the U.S. Ordnance Department. The bolt does not contain a firing pin and is simply used to seat the cartridge and seal the breech. It fires with a traditional side lock. Approximately 1,001 of these carbines were ordered on contract by the U.S. government late in the Civil War but were delivered too late to see action. It has small "M.M" (Miles Moulton) inspector initials on the left of the breech, left stock flat and top of the stock ahead of the buttplate tang, and a circled script "MM" inspection cartouche on the left stock flat.