What ammo are you shooting? Are shooting factory or reloads?
This time of year accuracy can get a little inconsistant, as the temps get higher. Ammo loaded with certqin powders that are sensitive to high temps, it can give erratic pressures and velocities, thus giving erratic groups.
As a long shot, it could be that year barrel has not been thoroughly stressed releived. you could have the barrel cryogenic treated to releive some of that stress.
