Call Smith and Wesson at 800-331-0852 at extension 2905. Give them the serial number and they will quickly give the year.
about 1919
It was manufactured in 1920.
That Colt police positive special with serial # 594826was manufactured in 1951.
Proofhouse.com has Colt sn data.
What is the manufactures date on an Iver Johnson revolver serial # Q18255
if double action revolver it was probably made about 1923
Proofhouse.com has Colt serial number tables.
1966
@1969
if your pistol is of the model 1911 with serial number 189558 then it was made in 1917 by colt. If it is the revolver then the serial number is to high for the 1917 revolver.
this question should be under Colt Firearms section
1970