I am trying a new load for my 243. I am loading in a winchester case, 115 jlk, with n165 powder. My question is should I use a mag primer or stick with the large rifle primer with this slow powder. I have shot a couple with 44.5 grains of powder and the mag primer and have not seen any pressure signs yet. N165 is a slower burning powder than H1000 I believe. Anyone load this combo or the like? I started off at 44 grains and the large rifle primer.