Hey, need help with this scope, was siteing my buddies scope in the other day, don't have anymore clicks to go on the scope. we need to raise the cross hairs up, its set as high as it will go, and is shooting about an inch low at 100 yrds. I'm thinking we need to shim the back scope base up a little to solve this problem. what can I shim it with ? ( aluminum foil ) any help would be greatly appriciated. thanks, Steve