Thats just insane. I shot a .50 cal and that will effectively crack your back for you. I read the comments below the video and I agree with some, it seems most of those individuals were not every day high power rifle handlers.. but man, that thing is a cannon.
That is probably what I looked like at 12 years old when my uncle handed me the .300 win mag. I knew how to shoot, held the gun, but I was pointing the opposite direction after I pulled the trigger. The recoil twisted me 180 degrees.