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your model 12 Winchester shotgun was made in 1924.
Your winchester model 12 shotgun was made by winchester in 1920.
Your winchester model 12 shotgun was made by winchester in 1937.
With the serial number that you have supplied,your Winchester model 12 shotgun was made in the year 1956.
your model 12 shotgun was made in 1956.
your Winchester model 12 shotgun was made in 1949.
If you are asking about a winchester model 12 shotgun(you do not say)?Then the serial number you provided indicates that your model 12 shotgun was made in 1923.
your model 12 Winchester shotgun was made in 1959.
your Winchester model 12 shotgun was made in 1923.
With the serial number that you have provided,your Winchester model 12 shotgun was made in the year 1956.
your Winchester model 12 shotgun was made in 1926.
your Winchester model 12 shotgun was made in 1948.