As I mentioned earlier, this gun is important in the context of the development of
the K-frames. It's the (original) Model of 1902, having straight taper barrel with
no shoulder at the frame face. Somewhere around serial 33000, perhaps late 1903,
the first engineering change to this model occurred. The frame face was thickened, as
was the OD of the barrel at the frame face. This resulted in a shoulder on the barrel,
right where it meets the frame. For the 4-inch barrels, this did not leave enough
room on the top of the barrel for the patent-date roll markings, so they were
moved to the right side of the barrel.

Here are two of mine, about serial number 45000. You can see the shoulder on the
barrel, and the patent date roll markings on the side of the barrel.



Regards, Mike Priwer