Ideal/preferred cartridge on species

[Longwalker]

How did the 257 Roberts fair on the black bear. Always thought they would be great for deer, but not bear, my seasons over lap so I carry my 308 Norma.

It was actually the quickest bear kill I've ever experienced. Dead where it stood. Bullet was a 115 gr. Nosler partition loaded to 2800 fps. Impact was broadside, high shoulder, bullet broke rear scapula, and spine, and far side scapula, and in the middle destroyed the aorta. Base of bullet exited. Shot was just over 100M. Correction - I did experience one other kill that was just as quick. It was two years ago, and a shot to the exact same spot on a smallish bear with a .375 H&H and 270 gr. Federal soft nose. Same results with a bullet twice as heavy and going nearly the same speed.