Colt M1878 Colt M1878 The Colt M1878 is a double-action revolver that was manufactured by Colt's Manufacturing Company from 1878 to 1907. It is often referred to as the "Frontier" or the "Double Action Army" revolver. A total of 51,210 Model 1878 revolvers were manufactured from 1878 to 1907, including 4,600 for the US Ordnance Department. These are known as the "Philippine" or "Alaskan" models. Samuel Colt experimented with double-action revolver systems, but he considered them to be unreliable. After Colt's patent expired in 1857, other manufacturers began producing double-action revolvers, but Colt's Manufacturing did not manufacture its own double-action revolver until
Colt Model 1855 Sidehammer Pocket Revolver purchased the National Arms Company in 1870. Actual original Colt models subsequent to the Sidehammer and inheriting a solid frame and a spur trigger were the Colt House (1871) and the Colt New Line (1873). The revolving mechanism of the cylinder was also used by Colt's in the following long arms, in rifle and carbine configurations: Colt Model 1855 Sidehammer Pocket Revolver The Colt Model 1855 Sidehammer, also known as the Colt Root Revolver after engineer Elisha K. Root (1808–1865), was a cap & ball single-action pocket revolver used during the American Civil War and made by the Colt's Patent