Just got by from a range session with the GP, a K38 Masterpiece and my K22. After sighting in from a rest at 50 ft I decided to try my hand at double action rapid fire with about one second intervals. I couldn't believe what this gun could do. My groups normally don't look anything like this.
Granted I was only using standard 38 spl 158 gr LRN but I was very happy with myself. I'm sure with full power .357 loads the group would be all over the place but the potential is there. Now I have to do my part and practice, practice and practice.
For comparison here's the K38 with the same loads from a rest.
I have 4 GP100s, and a few SP101S, for revolvers, Ruger is boss, IMO. You'll be very happy.