4227 will not give top velocity but it will give exceptional accuracy . If you want top velocity W296 / H110 will get you there also with very good accuracy . I use mag primers with both powders . 2400 also works quite well & is more forgiving in reduced loads than the other 2 . The trick is to keep any powder in it's preferred pressure level where it burns most effectively . Unique also works better at close to top loads for the same reason . Another powder I like is RS Enforcer / AA 4100 it too works best with mag primers .