On my list I have two SNs very close to yours, both 594xxx, which shipped 8/23/28 and 3/8/29. That range spread is not unusual, as S&W did not ship in SN order. Yours could have shipped earlier or later. The stocks on it are target stocks from a much later time, 1950s-1960s. I cannot see the left stock panel, but that pair could be fairly desirable. Does it have a football-shaped cutout on the top or is it plain? Some target stocks have a date stamped on the inside. You might check.
As noted, yours is called the Military and Police (M&P) model, which was the mainstay of the S&W product line for a great many years, and millions like it were made. S&W quality and workmanship was at its peak during the 1920s-30s. In the late 1950s, and after a number of internal engineering changes, essentially the same revolver became the Model 10. Don't be afraid to shoot it.