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I am surprised that this is from 1927. Its good condition led me to believe it would be from the 50’s.
Here are some things to look for in the future, regarding the general era of the .38 Military & Police revolver:
1. The "mushroom" shaped extractor rod knob. These pretty much went away in about 1927, being replaced by a "barrel" shaped knob. This eliminated one of the two cuts on the underside of the barrel. By late 1947, that also had been eliminated, replaced with a knurled end of the rod, resulting in no increased diameter at the end and eliminating the need to machine a notch on the bottom of the barrel. So a 1950s gun would not have a knob, just the knurled end.
2. The shape of the hammer changed dramatically in 1948, when the high speed hammer came into general use. Your hammer's spur is high on the hammer, coming nearly straight back from the body of the hammer. In the 1950s there would be a noticeable drop in elevation from the body of the hammer to where the spur takes off.
3. Just under the cylinder release (thumb piece) on your revolver is the visible, rounded end of a pin. This is the end of the threaded hammer pivot stud. On January 18, 1946, a management order mandated the replacement of this part with a pressed stud, which was polished off flat on the outside of the frame. No longer did you find the divot and rounded stud end showing on the frame's left side. All 1950s K frame revolvers would reflect this difference.
4. Patent dates on the barrel. These were pretty much gone by the end of 1948, although I have logged a very few that shipped in 1949, but those were certainly guns that simply sat in the vault longer than they should have. It is highly unlikely they were assembled after about mid-year 1948.
While I think DWalt is correct that your revolver probably left the factory in 1927, there is a slim chance it was in the prior year. S&W did not ship in serial order. I have, in my collection, an M&P serialized at 531xxx that letters to February, 1926. Since we don't know how fast these were shipping during those two years, and since they didn't go out in order, we have to allow some latitude in our estimates. Only a factory letter can nail the date down with certainty.
would being a 1927 in this condition put it in the $300 to $400 range?
I think that is about right. The original nickel makes it a bit more attractive than most that we see, but I suspect $400 is about tops for this one, given all the factors. Personally, I would probably draw the line pretty hard at $350.
I hope you find this post to be helpful.