The PA extended mount will raise the scope. I have a 1-4x20 in mine, and a buddy has a 3-9x40 in his. There is still about a 1/2" of clearance under the 40mm bell of his scope. I also have a 1-4x20 on another rifle that is mounted in the Burris mount and it and the PA mount are The same height. At 1x I can see the front site post in the bottom third or so of the scope.