Here's a couple of easy checks, never over look the importance primers can play, they can and do make a big difference, if anyone tells you otherwise they haven't shot enough guns, some guns it just does not make a difference, but others have a personality and make you work at it to find what it likes, but try this first, next time at the range shoot two groups of the same load, making sure all screws are tight, shot the first group, let the barrel cool, then loosen the rear guard screw or screws when there are 3, just barely snug so they are not loose, shoot another group, there can be something to learn here, never assume the rifle is bedded correctly, if nothing changes after the second group you know it's not the bedding, if the group moves more than a inch the bedding is incorrect, if luck is on your side you may find the second group has improved your accuracy, if this is the case the tightening of the rear guard is putting torq on the action and will need to be properly bedded.