I am hoping some of you can help me with my current issue. I have a win model 70 300 win mag with a vortex viper 6.5 to 20x50 mounted with a weaver extended 20 MOA rail and weaver grand slam rings. I am zeroed at 300 and I only have 20.5 MOA available which gets me out to 950 but not 1000. I thought I would have more adjustment so I need ideas on how to get there???? Also I have a 270 win with the exact same setup and I only have 9.5 MOA to work with which only takes me to 650. Bummed out is an understatement when the rifle will shoot .3 MOA groups.