It's funny but the size of many aviation fuel system fasteners (forged bolts)Grant,
From past experiences with sporters, I would start at 35 inch lbs but I would not go over 45 inch lbs. What you should do, using your Anschütz prefered match ammo, is to shoot at least 5 groups (you want to have statistical evidence) at 35 inch lbs, 5 groups at 40 inch lbs and 5 and 45 inch lbs. You should see that one of the averages is better than the others.
Paul