My Chapius 9,3x74R SxS was regulated from the factory with iron sights.
I have two scopes fitted to it in the Chapuis factory rings and bases. They are the EAW twist type. Both scopes go back to zero. The rifle did not need to be regulated, and shoots good to 300 yards on paper. I have killed game at 281 yards with one scope [coyote] and a little over 300 yds [kudu] with the other scope..
IMHO ALL double rifles under 40 cal should be fitted with a scope in QD rings.
I even wish my 450/400 had a scope.Someday it might.