I have a Colt revolver, serial number 129397 which was owned by my grandfather. The patent date on the revolver is not fully legible, but appears to be 1850 or 1851. I am an amateur in this field. I am looking for sources of help which might guide me to answering these questions.

How can I distinguish the earlier Navy model from the 1960 Army model. How can I determine when and where this revolver with its serial number was manufactured. How long were revolvers such as this in general use in the U.S. My grandfather ran a saloon in Southern Illinois from the 1870's until his death in 1917, and I suspect he kept this under the bar for use in the event of a major disturbance or robbery. Would caps and balls for it have been readily available after 1900?