make sure that you are using the same ammo on every shoot or you'll shooting will be all screwed up. next make sure that nothing is wrong with the gun if you have any doubt that it is the gun then take it to a gunsmith and if he's any good he figure out if it's the gun. some scopes are just screwed up from the begining i have had the same problem with a nikon scope it cost the biggest buck i have ever seen in my life because no matter what you did to it it shot 10 inches low. if you think it is the scope then call the company that the scope came from and tell them your problem and there will replace it for free except for the shipping. you might just want to try a different scope and see if you have the same problem. anyways good luck hope you get it figured out.