I found this video interesting...
Everyone talks about "Knockdown Power", but no one has ever really demonstrated it. While this video doesn't really answer a whole lot of questions, it is a fairly done video that might help dispel some myths...
Knockdown Power Video22 March 2014, 04:13
p dog shooterRichard Davis the inventor and founder of 2nd chance body armor.
Disproved this myth decades ago shooting him self with a 44 mag many times being shot with high powder rifle.
While wearing his vests. He stated many times a bullet doesn't have he power to knock you over and blunt force trauma is BS.
But you will get a nasty bruise with a 44mag.I would imagine something more serious if hit over the spine .I once killed a feral cat by a 45acp hit over the spine [no armor] and the bullet never penetrated the skin !