Scope Problem

[BMoe-RN]

I have a Weaver Grand Slam 3x10 Tactical scope on my AR. I had it in a Nikon 20 Moa base. Well it took the turret all the way down and was still shooting 8" high at 100yrds. Not enough internal adjustment, so I went and got a Nikon 0 MOA mount and the scope turret is still bottomed out, and now shooting 2.5" high at 100. This scope was on a 22-250 bolt gun and holds zero fine. It is still holding zero now on the AR, I just have to use the next mil dot up from the cross hairs.
Will a scope riser correct this, or maybe a shim in the front scope ring?? I need some suggestions.

Thanks

[AMMOTECH]

Let's look at a couple of things first:

1- @ what distance did you zero the scope? (25,50,100Y ??)
This will have a big effect on how high or low you hit at different distances.

2- Your mount- I'd stick to LaRue or ADM for a mount that you can trust.

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