What model S&W is this?

[jepp2]

looks to have 3 screws on the right side...

If it was a 4 screw, it would be on the front of the trigger guard. The 4'th screw on the side plate makes it a 5 screw.

 

[farmerjohn]

I think they went to that side plate around 1955 and would have started model numbers stamped in the yoke around 1957.
If so, they likely referred to that one as a K38-Combat Masterpiece. Very nice revolver!

Thank you fokes a bunch, I'm going to shoot it, going to load me up some coated 158gr SWC to about 850fps with unique or 231 and enjoy it, thanks John

 

[kneedtospeed]

All of the early Magnum calibers were recessed and pinned.
As stated above, the .38's were not recessed, but were pinned.
Pre-model number .38's were Combat Masterpiece (later M15), and Target Masterpiece (later M14).