This idea has bounced around for a couple of years now, I don't know of anyone who has had entirely satisfactory results. It is a 452 barrel, no sane gun maker is going to put a 41 cal barrel out with a cahmebr that will accept 452 bullets, that is a recipe for a big time lawsuit. I wonder if another way of getting thereis to simply rechamber to a 45-90 or 45-120, but use 452 bullets. Might require the making of a special die set to get the cases to have a proper grip on the bullet. Could be as simple as not using an expander, depends on the amount of neck reduction in the die. Just a crazy idea of another approach.
The problem with simply using 410 shells is that while they would stand up to 45 Colt pressures, they won't allow for the pressures you could use with modified 303 cases. Those would take you into 40,000-45,000 psi territory. A 250 grain bullet at 2000 fps+ would be flat impressive.
Better yet would be if NEF would make a 454 Casuel barrel, then all this would be moot. But no, they had to bless/curse us with a 500 SW, go figure.