They will work but you will have to trim the rear screws or they will bind on the bolt and you have to watch carefully as some scopes may not have enough elevation adjustment to accept the difference in front base height. .033 inches (Usually the height added to the rear base to create a long distance gun but the effect works in reverse if you add the height to the front base) over a 6 inch mounting space is 20 MOA Using a 46 instead of the 20A will cause you to loose over 57 MOA of vertical.
That said most Leupold VX-3 scopes mounted on a 20A front base are very near the bottom of their vertical adjustment. The Leupold VX-3 has about 64 MOA of vertical adjustment so the 45/46 combo will work with the Leupold VX3.
- No. of Base Length Hole Spacing Diameter Thickness
- 20A 1.168 .860 1.360 .127
- 45 .812 .504 1.050 .396
- 46 1.168 .860 1.290 .222