You will need to provide the serial number,model number if present,barrel length,along with th caliber you provided.
Email smith and Wesson for the answer
If you contact Smith & Wesson, they will give you that information.
1982
Made in 1979.
1952
1955 -1956
1963-65.
42 years old.
Made @ 1964.
@1973
Impossible to answer without a serial number.
Call S&W or acquire a copy of the Standard Catalog of Smith and Wesson, 3rd edition