I think that's a "virtual" .38/44 Outdoorsman. Note that the barrel rib does not align properly with the frame.
That was one of the first things I noticed about it. There is no bluing on the barrel pin indicating a possible barrel change or the pin being driven in and out.
Do the serial numbers in the shroud under the barrel and on the back of the cylinder agree with the serial number on the frame?
Not exactly sure where the number is your speaking of unless it is the number under the crane and no it does not match the numbers on the bottom of the grip frame or back of cylinder. The numbers on the grip frame and back of cylinder are the same. The grips are not original, it came with Jay Scotts the trader wanted to keep so we removed our grips and excahnged revolvers.
Jumping off subject. The grips I pictured it with came from a yard sale find about a year ago, cost me a whopping $1.00. The grips were in a Pachmeyer box marked $5.00. When I removed the grips from the box. I said "these aren't Pachmeyers" and she immediately lowered the price to a dollar. At the same yard sale I found another set of diamond K-frame grips. I put the K-frame grips on Ebay and they sold for over a hundred. Before you think I got lucky at the yard sale. Had I been five minutes earlier I would have beat the guy to the 5 guns he bought for $500. The five included an old Winchester lever action, German Luger, beautiful mint looking Browning shotgun, Colt Woody and a WW2 Jap souvenir rifle.
I see you also have the uncommon "drosophila" thumb release. Those are very rare.
I did notice the thumb release did feel different, actually feels better than my other S&W's
AFTERTHOUGHT: The shape of the hammer gives away that this is a postwar transitional gun with the prewar long action. I think it was probably a .38/44 Heavy Duty originally, and then someone reworked the frame top to add the adjustable rear sight. At the same time, the postwar ribbed barrel was screwed into the frame. I would date the original gun to 1949. The sight and barrel could have come along at any time in the next 20 or 30 years (or even more). The S/N in the ejector shroud could give us a hint as to when that happened. And was the company still numbering the undersides of adjustable sights in the late 1940s? If so, there might be another hint there.