That is, or is what would become the model 14 (depending on its age). If it is from 1958 of later when they started marking them with model numbers it would have "MOD 14" stamped in the yoke cutout under the barrel (visible with the cylinder open). If it is from earlier than that, then it would simply be called the K38 Masterpiece Target Revolver as guy stated above, and in that case it does not have original wood grips. You can tell because grips from before 1968 had a diamond shaped uncheckered area around the screw hole. The one pictured has the 6" barrel and Patridge sight - both standard features of the Model 14 (including the pre-model-numbered version). I also noticed that yours has a barrel and cylinder with the distinctive "plum" coloring (sightly purple) compared to the more standard "blue/black" color of the frame. Some factory guns experienced this finish issue, though it is more common for it to be seen on a refinished gun. What rollmarks I can see are nice and sharp, as are the flutes and edges, plus the hammer and trigger haven't been blued. Most likely not refinished, just one of the mismatched original finishes where the blueing on the cylinder and barrel turned a different color over time.
Very nice gun, known for their eceptional accuracy.