A Rupp is characterized by a wider butt, and a relatively shallow swoop to the Roman nose. The comb break isn't as sharp as other makers, like Moll, nor is the depth of cheek rest cut out. That said, in larger calibers, they CAN be cheek slappers. I built one in a 50, and with charges greater than about 50 grains it's watch out time.
My recent build is a Kuntz, the #5 gun on the KRA disc. Again a very shallow swoop to the comb, but a deeper cut out. It's only a 38 cal, so tough to tell if it ever even COULD be a cheek slapper.
