If you call S&W they will tell you when it left the factory. It could have been made a few months to a few years before that.
@ 1969
1980
@1977
Impossible to answer without the serial number.
1966-67
Impossible to answer without the serial number. You will have to call S&W
@1975
Need a detailed description
@ 1960
1969
The serial number C642424 was assigned to the Smith and Wesson models 10,11,12,45,Air crewman and there pre model variations.The year of manufacture for your serial number is between 1963-1964.
Either late 1800s or early 1900s