Ruddy you don't seem to make much sense. First you said you have to compare factory ammo to factory ammo to compare the different cartridges, (by the way is definately not true if you ever want to reload), then you say that if you add powder to a win mag (which is reloading) you can get up to RUM factory performane. That is comparing handloading to factory. And if you somehow are getting 1/8 in groups out of factory ammo that is pretty incredible and i also wouldn't reload. Kinda hard to believe unless you're using the best custom rifles.