About to start on a 243W, scout rifle with either an 18.5, or, 20 inch barrel. I want to run a 90gr and keep my MV as reliably high as possible... somewhere around 3,100 in an 18.5 or 3,150-200 in a 20. I saw some reloading data on an 18.5 inch 308, shooting 165's at 2710 and he wasn't close to...