The Colt 2nd. & 3rd. generation revolvers are basically Uberti's with Colt factory stamps on them, so they will need some "Dremel-work" in order to load conicals.
The Uberti 3rd. Model Dragoon will load the LEE conicals without modification, but then again, that's pretty far from the Remington you originally were contemplating...?
And I have not had the chance to try the Dragoon with the "Johnson & Dow" conicals.