I can't see running a 454 in any standard lever action--it's asking for trouble. But if you downsize the caliber and go to .357, lever actions seem to handle hot load pretty well, and my guess is that they would do so for 41 magnum as well (the 41 mag. might be the sweet spot for lever actions even though there aren't too many out there). If you get bigger than that, you are starting to get a lot of energy/pressure in a hot load.