You will have to call S&W to find out when it left the factory.
serial number 28402
Your serial number indicates that your Smith and Wesson model 18 was made in the year 1962.
No such serial number. The serial number is on the butt.
Your serial number indicates that your Smith and Wesson model 39-2 was made in the year 1976.
With the serial number that you have provided,your Smith and Wesson model 39-2 was made in 1976-1977.
With the serial number that you have supplied,your serial number dates to the year 1948.
You will need to add the model of Smith and Wesson to your serial number to get the correct year of manufacture.
@1957
Your serial number indicates that it was made in 1971.
With the serial number that you have supplied,your Smith and Wesson model 15 was made in the year 1950.
Your serial number indicates that your Smith and Wesson 38 special was made in the Year 1960.
Your serial number indicates that your Smith and Wesson model 59 was made in the year 1975.