Some years ago I turned a 1411 (Older Match 54 Prone Rifle) with a 26"bbl into a decidedly front heavy Standard Rifle using one of the Fajen thumbhole silhouette stocks. I skeletonized the butt, drilled out the pistol grip and gutted the forearm starting 1 1/2" forward of the action. Bedded from there back. (One other aside, here... if you cut wood, reseal. If you get them down this thin, it doesn't take a lot of water to cause warpage...) Get rid of the heavy pad, if any, and replace it with a thin rubber pad or glue on the sole of a flip-flop as suggested by Don. If you need more length use 1" aluminum tubing spacers. Don't know which BKL rings you were using, but I saved over an ounce using their #257 rings vs B-Squares. Since you're using a McMillan glass instead of wood, I don't know how much weight you'll save by skeletonizing but I'd try that prior to doing anything to upset an otherwise sweet barrel. Best of luck. Let us know how you come out.