The G prefix started @ 1968 at @869000. G series sn's starting with a 2 would not have happend until after 1982 or so and would have seven numbers.
You will need to provide the model of Winchester you are asking about,along with the serial number in order to age your Winchester and give you a year of production.
The serial number allows the maker to track production.
Your serial number places the year of production as 1978.
with the serial number that you have provided,your Winchester model 55 was made in the first year of production which was 1924.
With the serial number that you have provided,your Winchester model 74 was made in the first year of production which was 1939.
With the serial number that you have provided,your Winchester model 9422 was made in the first year of production which is 1972.
With the serial number that you provided,your winchester model 88 lever action rifle was made by winchester in the first year of production,which was 1955.
With the serial number that you have provided,your Winchester model 74 rifle was made in the first year of production which was 1939.
The Winchester model 50 was manufactured by Winchester from 1954-1962.If you supply a serial number,I could give you a exact year of production.
1954
Your Winchester model 1897 was made by Winchester in 1955.
Winchester did not keep records of the production of serial numbers by years for this model.I can say that Winchester started this model in the year 1955.The serial numbers began at serial number 1001,and finished at serial number 217,180.production ceased in the year 1963.If I had to guess as to when yours was made,I would say 1956.