I do the same thing with .303 British and .30-40 Krag cases, for .44 Mag (.220 Swift is also acceptable, but not ideal).
.41 Mag shot shells can be made from .30-30 brass.
Those are, of course, 'extended', 'bottleneck', or 'heavy payload' shells that extend into the cylinder throats. There's no need for the rifle cases, if you can fit your desired shot payload in a charged standard case.
"Such is the strange way that man works -- first he virtually destroys a species and then does everything in his power to restore it."