I bought a box of sierra 150g sgk's this morning to go with my new winchester brass for my .270. The 140's I was previously shooting were with my dads old remington brass that was crap. I couldn't stand it anymore. I figured I would shoot a heavier bullet since I want to take deer out to 700-800 yards with this rifle. I have H-4831sc, retumbo, Rl-22 for powders. Is there really any practical difference between h-4831 and the SC version?? Also, I think I'm going to be using federal 215 mag primer this time around. Good idea or bad?? I want a real accurate load with this bullet. Any suggestions are appreciated.