Swap the scopes and use the known good scope and see what it does. Many possibilities covered already. I have an 11FL that drove me nuts. Four inch groups with handloads that shot an inch and a quarter in a handi rifle. I shortened the base screws and action screws, floated the barrel, changed scopes, inspected the crown, etc. Turns out that my problem was the bolt handle cut-out was off. The stock started out as a right hand stock and they filled the original slot and cut a new one on the left side. Unfortunately, it was almost a quarter inch too far back. The bolt handle was binding against the front of the cut out. I found it only because my buddy put a rattle can paint job on the stock and I finally noticed the paint was rubbed off at the cut-out. I filed out the slot and that dog became a .75 shooter.