Telescopic sights
Scope power and price do not affect accuracy in categories >1”.
Threshold: I’ve had Weaver V9 and K10, Lyman STS, Unertl, Litschert/Davis, Fecker, Tasco and other scopes, many of which have been satisfactory for benchrest shooting. A threshold scope must be adjustable to remove parallax. (I have removed parallax from fixed objective scopes by adjusting the objective)
An example of a threshold scope: From Midway, the Simmons Whitetail Classic 6.5-20 50mm Adjustable Objective. Today, 8/7/18, $109.99, free shipping and a $20 rebate from Simmons. I’ve had 2, have 1 now on a Ruger Charger with a Kidd barrel. I took it to the range yesterday to check the scope, which is as bright and clear as a bell. The disadvantage of this and other threshold scopes is that W and E settings aren’t numeric, can’t be recorded. Easily.
When groups are >1”, a scope “better” than a threshold scope will not reduce group size.