Don't screw with COW. A waste of time and components. Just load with bullets and go shoot. Choose a powder and bullet. Start at the top of std. 257 loads and go from there til you find best accuracy, that'll be your fireform load. It'll be as accurate as formed brass and very nearly the same velocity. My fireform load used W760 and an 85/87gr bullet doing high 3700's with 28" barrel.
