Ive checked the screws, swapped scopes, tried reloading several different bullets, 160ttsx, 200nbt, 210tsx, 180nbt, also shot some factory ammo with 225 and 250 grain bullets. Barrel is floated and I have cleaned it down to the metal, doesnt make much difference. Occasionally I will get a decent group, then it goes right back to up to 3 inch groups (at the worst).