do these rounds even hold up to one another? i was wondering what you guys thought out there. i know that the 6 ppc is a very accurate round, but so is the 6x45. i am looking for an accurate round for the 100-300 yard range. mostly though in the 100's. i will be shooting out of a 16 inch barrel on an AR plateform. will the 6 x45 run with the 6 ppc at these ranges?