Action screws can be a huge deal if you haven't checked them. Factory specs are all over the place, but I have found torquing everything with an inch pound torque wrench heals many an accuracy woe. I always try and find what the factory of the stock recommends, but if that is impossible, I will torque to 60-65 inch pounds with synthetic, and wood stocks that have pillars, and 30 inch pounds on wood stocks without. I have seen this simple fix make a huge difference more times than I can remember, it's the first thing I do when I get a new or used rifle. It literally turned a Savage 110 Bat 338 LM into a one hole rifle that the owner had spent much money on ammo trying to find anything that would shoot a decent group. He brought the rifle to me and ask me to see if I could help it, and that was the first time I looked through a NF scope, bad, bad deal for me, expensive. I torqued the action screws to spec, and the thing literally stacks bullets into ragged holes at 100. I loosen both or all action screws, sit the rifle's butt plate on the ground making sure the action is seated firmly in the rear of the stock; run the screws in barely snug, and then torque the rear screw first and follow with the front. The method has worked in fixing several rifles for me and is worth a shot if you haven't tried it.
