Re: 338 lapua mag accuracy problem
This is a long shot. I once had a fatigued erector spring in a scope that caused accuracy problems when dialing at the longer ranges. As elevation is increased, the spring tension is lessened. A fatigued spring woukd apply very little pressure and possiblly allow movement of the tube. Very rare, but ruling out shooter error, and conditions, the fact that your shorter range groups are tight, and the components are identical, that leaves the scope. Easy to rule out by swapping the scope.
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