Colt Walker of Texas had been the major purchaser of the early Paterson Holster Pistol (No. 5 model), a five shot cal .36 revolver, and Samuel Walker became familiar with it during his service as a Texas Ranger. In 1847, Walker was engaged in the Mexican-American War as a captain in the United States Mounted Rifles. He approached Colt, requesting a large revolver to replace the single-shot Aston Johnson holster pistols then in use. The desired .44-.45 caliber revolver would be carried in saddle mounted holsters and would be large enough to dispatch horses as well as enemy soldiers. The Colt Walker
Colt New Line Colt New Line The Colt New Line was a single action pocket revolver introduced by the Colt's Patent Fire Arms Manufacturing Company in 1873. Two years after the Colt House Revolver (1871), a year after the Colt Open Top (1872) and almost simultaneously alongside the Colt Peacemaker (1873), the Colt New Line was one of the first metallic cartridge rear-loading revolvers manufactured by Colt's. It was, alongside the Colt Open Top Pocket Model Revolver (1871), one of the first pocket metallic cartridge revolvers made by the company. When the Rollin White patent for metallic cartridges firearms manufacture expired (c. 1870)