I popped on to your 50 section a little bit ago, and noticed that you had created a potentially unsafe condition in the process of lapping your scope rings. I posted part of the cure but based on dates, nobody has been there in a while. If you take a piece of 220 or so sandpaper and lay it grit upward on a flat smooth surface, and then massage the upper and lower ring flats on it, that will increase the space between the upper and lower ring halves allowing you to apply more screw pressure. If you feel that you may have lapped the rings into a mild oval, leave them off the gun, snug them onto the lapping bar, and turn the rings on the bar until you see at least 75% rub marks. Assuming they are barrett adjustable rings, which I have, now mount the rings on the gun and loosen the hex nuts. Now lay your scope in the rings and tighten the rings to the scope first, then tilt or level the scope as you like and tighten the hex nuts last. Do it any other way and you are taking a chance of kinking the scope tube. I use a nightforce 8-32, and tilt the front of the scope down with the elevation bottomed out until I am dead on at about 400 yards. Now I have all my elevation adjustment available to me if I want to reach out. Almost forgot, put nothing inside the rings such as tape which I have seen supplied with some brands of rings. This will change that crucial dimension that you create when you lap.