I can find no published information on differences between civilian and military versions of the Rogers and Spencer revolver. It appears that 5800 were produced, of which 5000 were delivered to the US Government in lots of 500 units, starting in January of 1865 and ending in September of that same year, 4 months after the cessation of hostilities in the US Civil War. I could find no records of delivery dates for the 800 apparently sold on the open civilian market, nor are there any records of design changes between the 800 apparently civilian guns and the 5000 military contract guns. The gun was apparently manufactured as early as 1863, using some of the same parts as it's predecessor, the Pettengill hammerless double action revolver. It is not possible to establish that a design change was made for use on the guns made under the military contract, but it is reasonable to assume that some small changes occurred over the 3 year production run, and that the high rate production run for the military contract tended to discourage changes once it began. Thus I would conclude that your "civilian" gun was made early in the production run and the "military" gun was made later, perhaps as one of the 5000 delivered to the government, but not necessarily so.
