I've got the wildcat cousin, 357 Herrett. It'll shoot 158 gr and 180 gr jacketed bullets equally well, about 1-1/2" at 100 yards. I've never tried it with lighter bullets.
I have a Lyman .35 caliber "M" expander die. I'll load 158 gr cast bullets over Unique for cheap practice rounds. I use the starting loads in Lyman's Cast Bullet manual for load data.
Mike Bellm says the .35 T/C barrels run undersize but I haven't slugged mine to see.