That is a hard one to correct without knowing a few more things.Do you hit your target where you aim at the range.Also try and shoot off the shoulder at the range after sighting in your gun.You might be dropping your gun and pulling it to one side.If so I would suggest either kneeling and using your left knee as a support if right handed or put the gun against a tree.Sometimes a support of any kind will make a world of difference.I will either sit and shoot if watching an area for a long time or kneel and shoot if possible.Also if you have a sling use it for support alot of hunters use it only to carry their gun as I did years ago big mistake.Good luck to you this year.