NATO ammo is how the round was meant to be, and still is,
todays American made regular ammo is watered down for the ignorant masses who dont invest any research in their guns, who just load up and and go so to speak...
you will also notice that European ammo is "hotter" generally than American ammo that isnt rated as +p. this is because they left the ammo alone, and we've watered it down...they dont load it hotter, they actually load it right.