I understand what you’re saying, but I’m sorry, I’m just not convinced that a 45 ACP round will knock a man flat. I don’t buy it. I think even a cast bullet, fully mushroomed, wouldn’t be able to reliably do that.
Nobody said a single round would knock a man flat. They said it would wallop him and likely make him stagger and lose his balance, and enough in succession would land him on his ass. :^)