For the 1911, 230 gr ball ammo is your best choice against bears. you don't need fancy expansion, you don't get hydrostatic shock (velocity's too low) but what you do need is penetration. what will go straight through a person usually won't make it through a bear. Also, never plan on a one shot kill. Think of the first round as getting the bear's attention. Second to slow it down enough to get a third, 4th, 5th 6th and seventh shot.