Mine has shot 1/2" groups from day 1. But I was shooting Hornady Superformance Match 75gr bullets.

Depending on whether your version has a wedge for the bedding block, you might need to make sure that the action is properly installed in the stock. If yours does not have the wedge, you might want to bed the recoil lug.

In case your not aware, the back screw on the trigger guard is just a wood screw, so don't mess with it. The action is just held in with the 2 front screws.