I have not used the .475 XPB, however I have used the 45 and 50 with much sucess. I have killed scores of feral hogs with these bullets, all with complete pass thru and evidence of massive expansion. The only bullet I have recovered was a 250 grain X. It was shot from a FA 454 Casull into a Sika buck. A Texas heart shot, hit 1" above "bullseye", went through almost 6" of spine and ended up under the hide of the brisket. The bullet measure slightly over 1.1" and weighted virtually the same as before it was shot.
The 275 grain .475 XPB is about the same length as the 400 grain Speer, giving it about the same Sectional Density. Comparing the 275 grain XPB at about 1500 fps to a 400 grain cast going about 1200 fps yields similar momentum and about 100 foot pounds more of kinetic energy. Enough momentun to penetrate completely on broadside and quartering shots.
The meplat of a cast bullet directs the energy away from the direction the bullet is traveling in an animal. The larger the meplat and the faster the bullet the more permanent wound channel damage that is done. The meplat of some better 400 grain plus cast bullets measure .350, a Barnes XPB that has expanded to 1.1" has a effective meplat of 1.1", nearly 10 times the surface area. Even if the XPB fails to expand at all, you will still have a .475 bullet with a high sectional density, a huge hollow point that will act as a meplat and a hole all the way though the animal.
Penetration of bullets of the same construction is controlled by momentum and sectional density.
Shot animals die as a result of the Central Nervous System shutting down, either as a direct hit to the spine or brain, or the loss of blood carrying oxygen to the brain.
Kinetic energy is the force that expands bullets. The bullets do the work of killing.
Cast bullets that completely penetrate kill Big Game, but a premium jacketed or X bullet that expands and completely penetrates kills quicker.
I think that people that only use cast bullets to hunt with will agree that the larger the hole(bullet diameter) through the animal the better.
