The top dog with respect to all out power in my stable is my 8.375" Raging Bull in 454. Topped off with high octane loads it only takes about 25 or so rounds to be done. That said, the load I have come to enjoy shooting, while still a handful, are the Lee 300gr RF loaded to the mid 1500fps range. They get the job done on anything I am liable to or have so far come across that needed their attention. I have various Contender barrels up to a 30-30 AI, and even though they have a significant pop, they simply aren't in the same ball park as the 454 loaded to top end.
This said however, my main squeeze when I hit the woods is my 7.5" SS Redhawk in 41 magnum. Plenty of everything to go around and easy enough shooting even with top end loads to have a ball on a sounder of feral hogs up close and personal in the underbrush.