I have both the Leupold Ultimate Slam and the Revenge and they are both great scopes. With the Leupold if you site your rifle in with your fifty yard target, you need to put the top of the circle as your point of aim at fifty. That will make the center of your cross hair line up at a hundred. Then the bottom of the circle will come back in at about 150 yards. This works for me with my setup. There is so many variations that a book could be written. The weight of the bullets the amount of powder the brand of powder can all change this. Get yourself a chrono and do some testing. Good luck