I have a Taylor arms branded uberti. Mine is .382ish and I bought a fatter mold from Tom. The uberti twist from what I read is set up for sub 300 grains. I am shooting 250-265 grains between my cast and commercial .381” bullets.
So check your twist which limits bullets and know what you want to do. I don’t think my gun will shoot 350’s for 1000 yards. I don’t plan on that anyhow. I am playing at 100-300 yards.