To find the year that any Winchester gun was made, you just need to know which model it is and what the serial number is (the model number and serial number are stamped on the gun itself). . Then go to this website and it will tell you when it was made:
http://oldguns.net/sn_php/winmods.htm
I'm trying to do the same thing, find the year of my model 1200 12 ga. Winchester magnum. I've used the oldguns site to get the year on 2 other winchesters but they don't seem to have the model 1200's on that site. I guess maybe model 1200's are not old enuf for oldguns.net :(
with the serial number that you provided,your Winchester model 12 shotgun was produced in the year 1935.
Your winchester model 12 shotgun was made by winchester in 1922.
your winchester model 12 pump shotgun was produced by winchester in 1942.
With the serial number that you have provided,your Winchester model 12 pump action shotgun was produced in the year 1955.
With the serial number that you provided,your Winchester model 12 pump action shotgun was produced in the year 1928.
Your winchester model 12 shotgun was produced by winchester in 1947.
With the serial number that you provided,your Winchester model 1912 pump action shotgun was produced in the year 1949.
Your serial number indicates that your Winchester model 12 shotgun was made in the year 1914.
With the serial number that you provided,your Winchester model 12 pump action shotgun was produced in 1942.It was one of 50,871 made that year.
With the serial number that you provided,your Winchester model 1912 pump action shotgun was produced in the year 1955.
Your Winchester model 12 shotgun was produced by Winchester in 1936.
your Winchester model 12 shotgun was produced in 1950.