About the dollar bill. I went to gunsmithing school and was taught the dollar bill thing there, I've heard it all my life. In gunsmithing school they teach you how to fix guns, NOT how to make them shoot. Now that I've learned something about accuracy I have absolutely no use for the dollar bill trick, it's actually WORSE than useless! Using such close tolerance certainly will not maintain clearance through the recoil cycle, instead the barrel will randomly bounce off of the forend material every shot.
IMO, if you want the rifle to look good, if you want close wood-to-metal fit, then do the dollar bill thing but add a pressure point at the forend. The easiest way I know to do this is to drop a glob of epoxy or silicone/rubber into the barrel channel and hang a weight from it.......a weight which corresponds to the amount of pressure you'd like to achieve. Elmer Keith and Jack O Connor actually agreed on this one
probably their only known area of agreement re rifles....downside of this method? When shooting slung any pressure will affect your point of impact.
The answer from an ACCURACY standpoint is very simple..............get enough clearance that you can't make the forend hit the barrel even with a smart rap from the heel of your hand. And I do mean a smart rap. Hold the rifle by the pistol grip, pointing up, and SMACK it with your open palm. Smack it straight up and down and also check for sideflex........sling up and see if you can flex the forend to touch or have an assistant slap the side after you're pressured up. (NOT your loverly wife!
) If you can get it to touch easily then it'll touch when you fire it. Clearance needed will be dependent upon material and bedding but I can't see less than 1/8" being enough.
That's how I see it, "form follows function" in my world.
al