As the owner of a firearm test range, I mount dozens of scopes each year. I get to see first hand how they perform, as well as the performance of scopes mounted by others. The two main complaints I hear about scopes usually center around those that fail to remain sighted in or group poorly on target. These complaints are usually very well founded. Most complaints about scope mounting are the direct result of poor scope-ring alignment and the accuracy-robbing stresses inherent between metal parts. These stresses pull and twist, causing the scope to move and to become misaligned. The scope never really settles down as bullet point-of-impact changes over time or even as a target group is being fired.

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