25-20 is a caliber, not a model number. If the gun is a lever action, it's probably a model 1892, which were made up until WW2. In that caliber, it's probably from the early 1900's. If you go to: http://armscollectors.com/sn/windates.htm select the proper model number and enter the serial number, it will give you the date the gun was made.
You do not state which model of Winchester you have? If you have a Winchester model 1892,then your rifle was made in 1917.
Your Winchester model 1892 lever action rifle was made in the year 1907,with the serial number that you have supplied.
Your winchester model 1894 rifle was made by winchester during the last 3 months of 1929.
1912
Your winchester model 1892 rifle was made by winchester in 1923.
Oliver Winchester made the first Winchester Rifle(repeating)
With the serial number that you have supplied;your Winchester model 71 rifle was made in the last year of production which was 1957.
Yes.The Winchester model 1876 rifle was the only rifle made by Winchester that was chambered for the 45-60WCF(winchester center fire).
With the serial number that you have supplied,your Winchester model 1886 sporting rifle was made during the last 3 months of 1897.
Your winchester model 1890 .22cal rifle was made by winchester in 1902.
Winchester made many rifle models chambered in several .22 calibers.
Winchester made the model 1873 rifle and the model 1876 rifle,but did not make a model 1875 rifle.