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
Revolver gate on the original Colt designs (and on nearly all single-action revolvers since, such as the famous Colt Single Action Army) is on the right side, which was done to facilitate loading while on horseback; with the revolver held in the left hand with the reins of the horse, the cartridges can be ejected and loaded with the right hand. Because the cylinders in these types of revolvers are firmly attached at the front and rear of the frame, and the frame is typically full thickness all the way around, fixed cylinder revolvers are inherently strong designs. Accordingly, many modern