Re: Should I lap?
I think the best way to put it is mount everything up and verify the alignment, the midwayusa alignment/lapping kit is well worth the money, and go from there. If you mount it all up and the alignment kit shows that the rings are in line, and the scope fits in them fine, then you don't need to lap. However on most factory receivers they have poor tolerances so the base bolted to them gets twisted a bit, and the rings get out of alignment. NO MATTER how expensive or perfectly machined the rings or base is. That translates to poor scope/ring contact or in very bad cases bending/denting the scope tube. Even a steel rail bends fairly easy, if you don't believe it take a quality steel base attach it at either the front or back and pull up on the other side, it doesn't take much force to flex it. Torquing the base screws can easily twist the base.
After that buy a torque wrench and properly torque the rings and bases, I'd be willing to bet that 99% of the problems people have with rings/bases staying tight and scopes moving are because they are not properly torqued evenly. It also saves you from denting the scope tube or stripping bolts/receivers by applying too much force. It's amazing how many scopes you see with brutal ring marks from guys ham fisting their rings.
For what we spend on rifles, the $80 for the alignment/lapping kit is cheap insurance, mount everything up, check the alignment, if it's good, mount the scope, torque the rings and be happy. If it's not then it's time to address possible causes, bedding the scope base, trying different rings, to get it as close as possible, then lap if the alignment is still a little bit off. If there is a major alignment issue lapping will not fix it, or if it does you may take too much material off of the rings and not be able to clamp the scope properly.
