There's no denying that epoxy will conform to any surface better than any pre-machined part ever could. As long as you use release agent on the receiver there's nothing to lose even if the surfaces do match well - with the epoxy, they will match perfectly. :) I've just never heard of using it under a base. I'm trying to recall if any of my rifles that do have one piece bases were installed by myself or if they are on the various used rifles I have that came with bases installed. I can't remember ever installing a one-piece since my preferred mount is the Leupold two piece with the front dove-tail and rear windage adjusting base. I've always used a screwdriver that I have which has a handle right about 1inch in diameter to turn in the front ring. I cringe when I hear people say they use their scope for that job. Then I sit the bottom half of the rear ring on the base and put the scope in it and use the scope as an alignment tool. If you adjust the windage screws carefully and evenly, checking with a bright light to verify the scope is sitting fully down in the rings, you can get a real good alignment of the rings latterly. If they happen to be of differing heights, you are out of luck with this method. I've yet to run into a situation where I could detect any gap between the rings and scope even with the brightest light. I've seen those alignment bars with the points that work like centers on a lathe but have always felt frustrated doing the same thing with aligning the headstock and a center on the lathe was not as precise as it is implied. I mean you aren't really measuring, you are just looking at two points that could still be off a thousandth or two and I'm not sure you'd see it. Now if you use the lapping tool, then by George, you can say everything is aligned!
