Sizing issues - Butler Creek Flip-Open Objective Scope Covers

Although I understand sizes can't all be matched, none of the scopes have been on size for some reason. I have 6 scopes, and all seem to be off. So a chart that says from 41mm to 42mm would be great. Not just one size. Because I picked the smaller, thinking the next size up will be too large. But the actual covers end up being too tight. So if it falls inbetween, I guess order the next size up.
Pros: Like how they work, and great price
Cons: Sizes fall inbetween measured scope

This review was written in the old system and had content requirements that are different than reviews written today.