The Palmer Model 1865 Carbine was manufactured under the E.G. Lamson & Company brand label to a W. Palmer patent secured on December 22nd, 1863. Lamson was based out of Windsor, Connecticut and handed the contract to manufacture the Palmer design on a quantitative scale for Union forces during the latter half of the American Civil War (1861-1865). The Model 1865, as it came to be identified, was notable in that it was a bolt-action system - the first such weapon firing a metallic cartridge to be adopted by the United States Army's Ordnance Department. Despite some 1,000 carbines believed produced, the type arrived too late to see combat service in the war. Hostilities formally ceased on May 10th, 1865 while first deliveries did not occur until June. As such, they did not see formal issuance to US Army forces.
Categorized as a "carbine", the weapon was primarily intended for mounted troops who could realistically and effectively wield a typical long gun of the period from horseback. The carbine was, therefore, designed as a shorter alternative, retaining all of the function of their long gun brethren while utilizing a shorter forend and barrel (though at the expense of some useful effective range). This provided the same hard-hitting firepower of a rifle within a more compact, transportable form (the alternative being a pistol or sabre). The carbine could just as easily be issued to fast-moving ground troops for skirmishing as well.
Outwardly, the Model 1865 was an obvious product of the period utilizing a wooden stock with inlaid metal components. There was a slightly-angled grip handle with integrated shoulder stock and the wooden body making up the forend. The barrel and forend were joined by a single barrel band, the barrel protruding a short distance ahead of the bulk of the weapon. The hinged hammer arm sat along the right side of the receiver within each of the primary hand with the bolt-action handle seated along the same side though at the extreme rear of the receiver. A sling ring arrangement was set upon the lockplate on the left side of the weapon. The barrel measured 20 inches long and consisted of a blue casehardened finish while the stock was walnut.
The Palmer design was unique in its use of the bolt-action system - a system still common to many sporting, police and military precision rifles today. A quarter-turn of the handle unlocked the bolt to which a rearward pull was used to extract any spent shell casings residing in the chamber. This then opened the breech for reloading. The hammer was manually cocked and released through the trigger pull as usual. The trigger unit lay under the receiver in the usual way complete with curved trigger assembly and oblong trigger ring. The weapon was chambered for the .54 rimfire cartridge and was of a single-shot design.