The Model 1855 was manufactured from 1856 to 1864 with a total production of a little more than 4,400. The top strap is marked "COL. COLT HARTFORD CT. U.S.A." , the serial number is marked on the bottom of the frame, a cylinder flute is marked with the Sept. 10th patent date and the left side of the frame is marked "COLT'S PATENT / unreadable". In addition the right side barrel is marked with the French "star / E" over the Belgian perron mark over the Belgian "crown / R" proofmark. One of the cylinder flutes is marked with the Belgian crown over oval containing "E / LG / star" proofmark. The right side of the frame at the breech is marked with the "star / E" over the Belgian perron mark. It is equipped with a brass blade front sight and a two leaf folding rear sight marked "300" and "600" and "100" in the center. All parts were blue except for the hammer and loading lever which were casehardened and the trigger guard is brass. Saddle ring and stud mounted on the left rear of the frame. The stock is straight grip with an iron buttplate, short forearm and buttstock compartment.

Period (possibly armory or arsenal) refinished with most of the finish remaining. There is a mix of blue finish and smooth brown patina on the left side rear of the frame. The buttplate has a smooth grayish patina. The trigger guard has been polished and remains shiny. There is a little minor pitting on the hammer. The loading lever retains half of the fading case colors. The wood has been refurbished and remains in excellent condition with a few minor dings in the forearm and only light handling marks on the stock. Some markings are faint while the remainder are clear. Mechanically fine. An interesting Model 1855 Revolving Carbine with interesting European proof markings.