Dick that little screw in upper right hand corner on the rear mount can need minor adjustments from time to time. What I do is secure the barrel in a padded vise and put a dial indicator on top of the end of the bell. The magnet base is attached to the flat on the side of the vise and I then start clicking the elevation adustment and watch how far the indicator needle moves. If not equal going through at least a full turn I then tighten that little screw until it does. I then move the indicator to the side of the bell and check the same for windage. If done right it will turn a bad scope into a very good one. That is if the lens are not separating and quite typical but easy to see if so and the spring and plunger are moving freely. It is also wise to check the fit of the front mount to the Pope Rid and easy to correct if needed. I hope this is somewhat helpful and as you said the bases are very prone to burrs developing if over tightened and simple enough to just stone them off.
heard of.
JLouis