Smith & Wesson Military & Police Hand Ejector, Model 1905 4th Change Caliber .38 Special Serial number 542XXX
References:
The Standard Catalog of Smith & Wesson, second edition, by Jim Supica and Richard Nahas, c. 2001
p. 292 241704 through 70000 produced 1915 – 1942.
p. 102 Factory records show that “a small number†marked “Texas State Prison†scattered between serial numbers 50000 and 630000 were purchased 1927 – 1930.
The Knight revolver was probably produced in the 1927 or 1928.