Whats the right "trim to" brass OAL for the 6.5 Grendel? Also I know i asked this question before but I see it says to use <span style="font-weight: bold">Magnum </span>small primers for the 6.5 and i cant find them anywere but i do have aton of CCI BR-4, CCI #400, Federal Small match(GM205M), Winchester small primers, Magtech 7 1/2 small primers. Which one of these would work best?