I am no ammo professional, and am somewhat new to guns so correct me if I'm wrong...
I'd rather use a hollow point that I know will expand and come to a stop INSIDE the targets body, rather than send a high velocity FMJ round THROUGH the target, through the wall of my apartment, and take out the neighbor while he's taking a late-night dump.
Dont assume that just because it's
designed or intended to expand and stop, that it will do so. There are so many variables that keep that from happening with most makes and types of HP. IF/when it works as intended, great. If it doesnt-
which is more often than not, then the round ends up acting just like an FMJ ball anyway.
When HP does work as intended, it often does so
too well. Expands and loses its momentum
too early, before it has penetrated deeply enough to reach anything vital.
It's also something of a myth with FMJ that it goes through-and-through all the time. Most center-mass/torso hits dont, actually. Some extremity hits sometimes do,though.