Bill, 15000, 17000 and 21000 serial numbers are hammer guns starting in 1886 with the introduction to the Hammerless gun. In trying to do research for Hammerless guns this is what I found out by looking at auctions and luckily most had pictures and in the description said hammers and or hammerless. I believe that is this case the 14000 range would be 1885. The earliest Hammerless serial number I had was 16211 also from Russ and 16272 from Brophy's book a photo comparing the breech balls of Syracuse and Fulton. I have serial numbers for Hammer guns from Russ Ruppel's research that start at 10377 and that information is on this site on Volume 3, Issue 3.