Based off your serial number your inherited .30-20 pre-dates my .32-20 M&P's which shipped 1912. I'll also take a guess that it has a round butt rather than a square?
A few pictures and/or a full description will go a long ways toward helping figure out just what you have. Additionally, you can follow this link
Weapon History Request - Smith & Wesson to request a historical letter on your gun. Current cost is $50.00, and should provide the exact shipping date and where it shipped to, sometimes even to the person it shipped to (Most seem to ship to a distributer).
Edited to add: The Customer Service folks only have access to the more recent guns. Any of the older guns, the best they can do is give you a very general range of dates it could have shipped. The best I can give you is 1903 to 1905 from the SCSW III.