.....All that said, black bear don't take well to being shot. They frequently die right there but not always, just like any game animal. Usually they'll just run off and die (let them die, don't pressure a wounded animal). Occasionally though you get a mean spirited beastie that kills 12 dogs and takes 20 rounds of high power rifle ammo at 10 paces to go down.
What rifle you shoot a black bear with is tremendously less important than making a good shot to the pump. Bringing oodles of horsepower really isn't usually necessary however, my personal favorite bear gun is a .444 Marlin because it shatters bones extremely effectively and keeps em' from running real far into the bush. Remember, black bear are not that big. A monster would be 500lbs. Most I have killed and seen killed are in the 200lbs class and don't need any more than most people bring for deer.
Hope for the best, prep for the worst.
The .44's work well, depending on your style of hunt, I'd move up to the 200 Nosler, if you know it's going to be close the 220 Nosler will work first time, every time.