I also know for a fact of being a Sniper for several LE agencies for now over 18 yrs, that an individual cannot sustain life for more than several seconds and continue with a placed shot into the heart from any high powered weapon due to the kinetic energy displaced into the chest area and central nervous system
I have personally shot a hog with a with a .308 using a 165 grn Nosler Bal. Tip at 2200fps out of my Lone Eagle pistol at 37 yds and travel over 150yds with both lungs and heart blown out!!!!
Which story are you stickin too? LOL