First step is to have some one else shoot your rifle and see if it will group. If it does you have a head problem. If it doesn't I would try a swab of an ammonia based cleaner( house hold ammonia works great) let it sit in the bore for 5 minutes them re swab. If it comes out blue/green you still have copper. If no copper ,check for a loose scope, and or bedding problems. What about the ammo? do you use the same stuff at the range that you use in the field?