Magnaport says they will modify an N-Frame Square Butt to a Round Butt K-Frame grip for $95.
I have small hands. The backstrap of the N-frame square butt doesn't bother me, but the front edge sticks out further as well. I love shooting 44 specials from my Model 29 (not so much 44 mags!), but would also love to have a grip closer in size to the K-frame.
Has anyone had any experience with having this done? If so, would you recommend it or not?