Because Smith & Wesson numbered frames before they were made into revolvers, it's impossible to get an exact year on pre-1970's guns in most cases. A numbered frame could sometimes be made into several models, and individual guns were sometimes shipped years after the frame was numbered.
However you can get exact information - if you are willing to pay S&W's in-house historian (and the company) a reasonable $30.00 search fee to look up the gun in the old records. This can be a lot of work, because the old books have not been conputerized into a database, and guns were not shipped in order of serial numbers.
Anyway, in this case you seem to have a .38, 1905 Hand Ejector -4th change, which was also known as the Military & Police model. An approximate date of manufacture would be during the late 1930's.
Also look and see if the gun's serial is stamped on the underside of the stocks - which would prove they were original to the gun, and increase it's collector's value.
