First, do NOT use Plus P ammo in that old gun. I think it'll be okay with std. velocity ammo and mid-range wadcutter loads.
The gun is a Military & Police, model of 1905, to distinguish it from the round butt version, Model of 1902. You probably have a Third or Fourth Model of 1905. The serial number will tell that difference.
From 1902 to 1915, as various small internal mods occurred, the model varied, as the gun evolved. You want the Fourth model, which remained the same until 1948, although WW II military examples, called Victory Model, had dull gray finishes. Some here say the Fourth Model ended in 1940-41, but apart from finish, only one change occurred prior to 1948.That was in Dec., 1944, when a new internal safety bar was added. A sailor dropped his Victory Model on a ship deck, and the gun fired, killing the man. The Navy wanted that problem fixed, and it was. Should have been done a generation before!
The gold grip medallions suggest manufacture during or before WW I! Cylinders weren't yet heat treated. I think that happened about 1919-1920. A specialist collector here can even give you the serial number when that change occurred. It was well beyond 316,000, but under 317,000.
I don't know what your dad paid, but as an old gun with nostalgic interest, it's sound. You can even use the modest loads cited. Condition looks pretty good, although not so pristine as to excite a collector. I guess he didn't get the original box? Buyers usually threw boxes away, but they interest collectors, a lot.
Stand by. Someone will tell you more, based on exact serial number. You need to post the entire number.
What was the price? If over $250, probably too much. This is a very common S&W, one of their iconic models.As a nostalgic gun, I'd like to have one. For a modern general service and defense gun, I'd buy a much later one, Model 10 or better, Model 64, which is stainless.
