I finished off a deer with Win Ranger T Series 230 gr +p out of my Kimber last year, and was very underwhelmed with the penetration I got. Most 45 ACP hollow points are made for self defense against 2 legged critters, not 4. The hair and skin of a deer is alot thicker than a human, the bear will be even thicker with more fat, muscle, and bigger bones. The 10 or 357 with hunting bullets would be a better choice. If all I had was a 45, I suppose I would carry 230 gr Buffalo Bore +p flat point FMJs. That way I know it will at least get into and maybe through a bear.