I have seen griz shot with the 300 win mag and wasn't too impressed. My moose/bear guns are as follows, 338 RUM with 225gr Accubond @ 3150fps, 9.3x62 mauser with 286gr Nosler partiton @ 2400fps, 375 H&H with 300gr Partitions @ 2550fps or 270gr Barnes TSX @ 2700fps, and 45/70 with 405gr Kodaik bonded @ 1925fps.
Anything bear worthy starts at 338 WM and goes up from there. If people are recoil sensitive they would be better served with something that shots a heavy bullet at modest velosites. 338/06 w/250gr, 35 whelen with 250s, 9.3x62 with 286gr, all have moderate recoil and are very effective out to a couple hundred yards. Premium bullets are a must.