As noted above, start with just a shim under the lug area.
Also make sure that wood is still not touching the barrel anywhere.
If no improvements doing this, you have other issues.
If the box is not free to move a little, it may be adding a pressure point you do not want.
If the bolt is touching the stock when locked shut this is also a problem.
If none of this helps, a couple inches of bedding in front of the lug area may help.
If none of this has helped, add something to regain the pressure point at the end of the fore end.
Have you done any load development?
Tim
