Colt brought about their New Army Model revolver in 1860 and it quickly proved itself the definitive combat revolver of the time. Designed to succeed the Colt 3rd Model Dragoon series of revolvers, the Model 1860 was essentially a re-envisioning of the Colt Navy Model of 1851 which, itself, proved a success with US Army forces despite the designation (originally intended for US Navy personnel). The New Army Model 1860 was produced in the hundreds of thousands owing much to the bloody conflict that was the American Civil War as the US Army standard issue sidearm and went on to become one of the most recognized and popular handguns of the war. Beyond its use in that conflict, the Colt New Army Model 1860 figured prominently in the Indian Wars to follow.
Like other Colt developments, the Model 1860 New Army was of single-action in design, meaning that the operator needed to actuate the hammer to cock the weapon which rotated the cylinder to the next available ammunition chamber. Only then could the user squeeze the trigger and complete the firing action. Each successive shot needed to be cocked in this fashion. Outwardly, the New Army Model revolver followed much in line with previous Colt offerings including the "open frame" receiver which was used to describe the lack of a supporting structure over the cylinder proper. The barrel was naturally fitted ahead of the cylinder and well contoured. Underneath the barrel ran an integrated ratcheting loading lever which was used to ram the firing chamber contents down towards the percussion caps. The user pulled down on the loading lever to which an arm, acting as a ramrod, would move rearwards towards each bullet chamber and force their contents into the cylinder. The action on the slightly oversized ball rounds also trimmed some of the lead off and effectively sealed each chamber. This sealing was important as to prevent ignition of powder residue across the mouths of the other chambers - this could lead to a cylinder rupture or severe injury for the user.
The weapon was loaded first with 35 grains of gunpowder in each cylinder (via a flask carried by the operator) and then a .44 ball was added as ammunition. These were added to each chamber (from the front end) and rammed home by the loading arm. Percussion caps needed to be set at each chamber rear along the cylinder rear on provided nipples. Once cocked, the weapon was then made ready to fire. The user could let off six rounds before requiring a reload. Alternatively, soldiers could be issued "paper" cartridges containing both the preset amount of gunpowder and the ball bullet in a single handy container. In this fashion, the user needed only to enter each paper cartridge into each chamber from the front and ram the contents down with the loading lever. Percussion caps were still required at each chamber rear.
Other physical features of the revolver included a fixed iron sight provided aft of the muzzle. The hammer spur protruded upwards and away from the receiver to allow the thumb to manage its action. The pistol grip - covered on both sides by a beautiful walnut finish - was ergonomically curved and smooth to fit firmly in the firing hand. The thin trigger unit was set within an equally thin trigger ring. The cylinder was either fluted or un-fluted while the frame of original models was completed from steel.
In practice, the New Army Model 1860 saw widespread use, particularly during the American Civil War (1861-1865) which marked a production boom for the Colt Manufacturing Company. The initial 1,000 or so production-quality models were completed with 7.5-inch barrels but most were eventually seen with the more popular 8-inch barrels from there on. Not only did it see action with Union forces but the Confederates noted its robust and effective value enough to produce illegal local copies all their own. As a military sidearm, the New Army Model 1860 was everywhere battles were waged. It served as a sidearm to officers, infantry and cavalry personnel as well as second-line units. Some military versions were even fitted with an optional wooden shoulder stock (about as long as the pistol itself) to assist in a three-point stabilization system when firing, leading to reported accuracy benefits at range.
All told, some 200,500 examples were produced during the span of 1860 and 1873, most with the aforementioned 8-inch barrels. Of these, 127,156 were produced to fulfill the US government contract during wartime.