So why has the 6.5-ounce 2.5x Leupold M8 that's been on Phil Shoemaker's relatively lightweight .458 Winchester Magnum managed to retain zero for decades now?
Well, as with most things, a single anecdote doesn’t prove a concept, but I would say that the scope in question has retained zero despite being lightweight, not because of it. I think you would agree that a 7 lbs rifle/scope combo is harder on the scope than a 9 lbs rifle/scope combo.
The fastening of the internal parts, relative to their weight, must be fairly exceptional.
