Brian,
it's a *&* "PC-13", a Lew Horton special that was only made to the tune of 300 copies back in 1995. It's a Model 13 with a 3" heavy barrel, DAO converted and hammer bobbed, quad-ported barrel, chamfered charge holes, Dymondwood grips and a tuned action. I found it in unfired condition at a Knoxville gun show a few weeks ago....I'd been wanting one ever since I started collecting nice *&* wheelguns, but I never thought I'd even see one in the wild.