Do NOT lower the rear mount by milling or you will move the slot for the claw slider downward absolutely ruining it! If you shim at all, let it be inside the rings, assuming they are not soldered on. Replace the front dovetail at your option. It could be that the scope is the problem--can it be replaced? Often, drillings and other regulated arms must be handloaded till the shot is adjusted to the sights without regard to anyone wanting that extra 100 fps. A dead deer won't know the difference between the two anyway. I would try to get the load to be accurate with the iron sights and then be also doable with the scope. Der Ami may be right about trying heavier bullets...Steve
