I'm going to build a dedicated Varmint AR w/ a 20-inch barrel. I was wondering what kind of groupings I might be able to achieve w/ hand loads and say an E.R. Shaw, Wilson arms, RR or other manufacturers barrels. Should I go with a wylde camber and shoot heavier bullets or will 50 to 69 grain bullets work as well on varmints on up to the size of yots? 1:9, 1:8, or 1:12 twist?