I've used Trail Boss with considerable success in the .500 Mag. 12gr behind a 405 gr hard cast produces a very mild recoil but a satisfying thump at the backstop.

I'm also getting good results in my .458 Win Mag using 23gr behind a 300gr cowboy bullet.

Hodgdon says it has no position sensitivity and with normal charges, you virtually can't double charge a case. The only downside for light loads is that they cheap you out with I think are 9oz cans vice the usual 16 oz cannisters. Don