I have 3 Sauer 202 rifles in .375 , .308 and .243 . All have Apel mounts and I want to interchange scopes for differrent quarry. However at the moment none of the scope feet fit exactly between rifles . Is there any adjustment in the bases, and if so where is it . I understand that the .375 might be a problem as it is a magnum action but I would expect to be able to swap between the 2 standard actions. Any help / advice greatly appreciated.