Want to say "hi yall". I've been monitoring(lurkin) for a couple of weeks; maybe a month now and since I'm not a LR hunter or shooter(just doing some learnin)I haven't had need to register or post. Maybe I should put this subject in the "Optics" forum, but being it's my first post, I didn't want to "contaminate" the long range format. I just acquired a Marlin Model 30 30-30. Neither long range or expensive, infact I traded for it. It'll do what I need to do. ~150 yards max, but I gotsa slight problem mounting a scope on it. I bought a low base and Weaver style rings for quick detatchment if needed. I prefer open sights, but others of the family(primary users) prefer scope. Problem: when mounted it shows over 40 MOA shooting low. Kinda confirmed it with 25 yard range test. Shootin at a large targe, hitting below the target. I switched the rings around and also was able to reverse(end to end) the base; to no avail. I put two paper shims under the rear ring and two under the base mount. Brought it up about16 MOA. I really don't want to turn the turrets to get 18" at a 100 yards or is this ok? Cheap scope also. Question: can I continue with the shims without undue instability or should I persue another venue? I have no qualms about doing some judicious filing on the bottom of the base and polishing up and re-blackening with Aluminum black. Would this be viable? I come here cause I KNOW you guys shoot and know your equipment. Thanks.