Im not even gonna account for how almost meaningless loss of a limb or tow is for them. So id guess you could shoot like 10 shots into a radscorpio head before you bring it down. You surly played with insects as a child at some point. Like, insects should be god-awefully hard to kill. Damn, this will make me start a damage mod myself since non i like so far.
Ghouls could be exceptions since apparently, they cant suffer brain damage even though their brains are exposed etc, so i guess internal organs are more resistant to damage. So to counter that fact and balance it out, id be increasing it to 3-5 shots on humans/humaniods. Its difficult to measure with fallout games because they dont offer any way of torso sub-parting. Although, one shot torso is a bit much, but 3-5 shots should do the trick. Most often then not, even with modern medicine etc, a gunshot to leg or arm can end up in amputation in like 50/50 chance.
You can count them on the hands who survived multiple gunshots to the torso etc, but those are extreme exceptions.
Uhm, may i add that a few you can count on hand people who survived some odds can not be counted for.
