Had a Weaver Grand Slam 3x10 that was recommended here in the past on a 22-250 for coyote hunting. Well I got an AR with a 20MOA base (Nikon) and installed this scope. It took all of the down adjustment and was still shooting 8 inches high at 100yrds. Then I went out and bought a 0 MOA Nikon mount and with the scope at the lowest setting is still shooting 2.5" high at 100. Any suggestions?? The scope is holding zero and always has. I just don't understand why it isn't going up in elevation when using the 0 MOA.