5 years
Your serial number indicates that your Ithaca shotgun was made in the year 1920.
It sounds as if you have a Ithaca Crass model shotgun,that was produced in the year 1903 by your serial number.
1924
Impossible to answer without the serial number
It was made in 1919.
612
Impossible to answer without the serial number
1905
about 1925
With the serial number that you provided,your Ithaca double barrel shotgun with the damascus barrels was produced in the year 1900.
A model 37 with the serial # 10464 was produced in 1939.
The Ithaca Model 37 shotgun with the serial number 371193174 was manufactured in the year 1973. Ithaca shotguns typically have their production dates determined based on their serial numbers, and this particular number falls within the range that corresponds to that year.