With the medium speed bear protection rifles such as the 450 Marlin or the 45/70 the heavy hardcast seems to be the bullet of choice. I understand that penetration is needed, but what about hydrostatic shock, and explosive wound channels?
Slow and heavy penetrates soft tissue, where hydrostatic shock performs best, but hard cast are used for slow and heavy. If slower works better in this medium, what about smashing large bones, joints, and the skull? Would not a faster bullet smash the hard stuff better than the slow one< it is physics, not magic I would think.
If the purpose is Protection and stopping a charge--not hunting, the bullet coming out the south side of a north headed bear may a moot point if the bears lives long enough to eat you before expiring. This is why this subject (bear protection) is so elusive, as rumors, theories, and a spiritual numen seems to follow the subject at hand. The modern bonded softs like Swift, and Trophy Bonded stay together and penetrate enough to kill in most situations I would think. I shot a 600 pound Black Bear in Northern Alberta with a .338 using a Swift bullet and it did a great job! But, and there always is a but in life, that was not a charging shot.
I am leaning on researching putting a soft up first in the chamber, and hardcast behind it. If the soft doesn't stop it, or if I only get one chance to shoot, I trust a good bonded soft to make it die sooner than the hardcast. But, if I get a second shot to back up the first one, then the solid can bust up its wheels to slow it down more...
This is for the 450 Marlin. My .458 Lott will probably only use Trophy Bonded bullets for bear. Maybe Swifts, I will wait and see how they shoot in more focused and intense shooting sessions first.
Sound good to anyone with experience? Remember, I am talking about a carry protection rifle at this time, not hunting with it.