There is very little difference between the two ballistically as far as windage and trajectory are concerned as they have nearly identical BCs. There is only a slight advantage in energy with the 284 as the heavier weight bullet accounts for more down range energy but it does so using more powder and generating more recoil. If you really want to beat a 6.5 by any substantial margin you have got to use a 180, and again generate even more recoil with a heavier bullet to do it.
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