You don't know what you're talking about--and the big problem is that you apparently don't know two things:
First, you believe so much in the sectional density of the bullet as its sits in the cartridge, that you apparently have never realized the sectional density of an expanding bullet changes as soon as it starts to expand. This is why the frontal area of the "mushroom" affects penetration as much as retained weight. Bullets that expand widely will NOT penetrate a deeply as bullets that result in a smaller mushroom, given the same original weight, sectional density and impact velocity. This has been proven many times both in "media" and on game--and it's true not just because of the increased resistance, but the fact that a wider mushroom tends to make the bullet less stable in tissue.
Second, you obviously are not aware that the larger-caliber, heavier Nosler Partitions have the partition moved forward to retain more weight. This is true of Partitions from the 286-grain 9.3mm on up, which is why they penetrate very deeply. I have recovered only a very few of these, because they do indeed mostly exit, unless the angle is extreme on very large animals. The average retained weight of 286 9.3s, 300 .375s and 400 .416s in my collection is 89%, and with their smaller (but still substantial) "mushroom" they do indeed out-penetrate bonded bullets that open up wider. Which is exactly what pabucktail is talking about.
But go ahead, keep pestering people like pabucktail and Phil who (unlike you) do have experience on big bears.
