"Your" Winchester Model 21 Double Barrel Shotgun was manufactured in 1933, giving it an age of 77 years, as of 2010.
Please include the model number of your Winchester shotgun to get a correct answer to your question along with the serial number.
Check the receiver and barrels.
Impossible to answer.
Check the receiver and barrel
By the specific serial number stamped into the frame.
You will need to include the shotgun model number,or model name.Type of shotgun(single shot,pump action,double barrel,or semi-auto)along with the serial number that you have provided to get the correct age of your Winchester shotgun.
With the serial number that you provided,your Ithaca double barrel shotgun with the damascus barrels was produced in the year 1900.
Check the receiver and bottom of the barrel
From what I could find your gun is made by Winchester. It should say it on your gun somewhere though.
1896
Look on bottom of receiver and barrel
27p