With regard to calibre, this is a specious argument. I have seen the effects of both round on a human body. I would NOT want to be hit by a .45 anywhere on my person. I have also seen people knocked down by the .45, so his other argument is lacking.
I have owned .45, 9mm and currently own a .40. I plan on going back to .45 this weekend.
That's what I thought too. Hit someone in the breastbone with a .45 or a .44 mag and they are going over.
Not to mention a rifle or shotgun round...and neither one of them has knocked me backwards since I was eight.
While it has been advocated by many-a-misinformed-gun-counter commando that some sort of energy transfer occurs between a projectile and its target, this has been rejected by everyone ...
There absolutely is an energy transfer between the bullet and flesh. Anyone who has ever butchered a deer has seen the massive hemorrhaging that takes place. This damage occurs in flesh that was nowhere near the actual path of the projectile. When a bullet hits flesh, a pressure/shock wave travels through the surrounding flesh. The reason you want an expanding bullet is not so much to cut a bigger path through the body. It is to slow the bullet down more so that it imparts more of its energy into the target.