you just need an 8. mm to the chest and your gone.
I wasn't aware anything aside from the Nambu even used an 8mm cartridge.
It's typically referred to as .32, not 8mm, and a .32 to the chest wouldn't kill you. It's far too small, unless it punctured your heart (but I assume you mean center of mass, not aiming for a vital organ. It'd only be lethal to the chest if you didn't receive medical attention, otherwise. Even a 9mm cartridge is sketchy at best, it really depends on where you shoot a person.