David

I think this is a much rarer gun than you think. I bet it has a screw
in the front of the trigger guard, making it a 5-screw frame. The last of the 4-screw frames is about s/n 62XXX or so.

If I'm right, this is one of the 10,000 (or so) transition K-frames, that
has the 5th frame screw, but the old levering trigger rebound lockwork.

In this one instance, I have to say that the Collectors definition of
calling this a Model of 1905 is more illustrative of what it actually is -
even though (because of its round butt) it does not meet the factory
definition of a 1905. Of course, I can't call it a 1905 !

Its worth a lot more than you think !

Check out that first picture - you can see the head of the 5th frame screw, in front of the trigger guard.

Regards, Mike Priwer