How old is your 20 gauge Remington model 17 pump shotgun serial 7018?

The Remington Model 17 pump shotgun was produced from 1921 to 1934. Given that your shotgun's serial number is 7018, it likely falls within that production range, making it approximately 89 to 102 years old, depending on the exact year it was manufactured. For a precise age, you would need to consult Remington's production records or a firearms expert.