Hydro-static shock does indeed exist.Lung shot deer's internal organs fall out during dressing in one clot with high velocity #'s like .220 Swift/22-250 and even .223+.222.Picture hypothetically your bloodvessels being able to withstand 40psi then introduce a projectile at 3-4000 fps instantly changing the preasure to change faster than the vessel can handle.Like shooting a full soda can instant mist with both ends blown outward and a pencil hole through the centre.Shot placement and penetration to the vitals is required.I use the above calibers as example only although I've used them and never lost an animal.I forget which gun writer said it but to settle a disagreement on bullet performance quoted " at what point of the animal's death did the bullet fail"?Use what has worked for you as we all form opinions based on our own experiences.It becomes a Ford/Chevy debate like brand loyalty.........Elmer Keith and Jack O'Conner used to get into heated exchanges and they both shot a lot of game Worldwide..........Harold