Rosewood or ivory handled screw destroyers.

With oil bottle to match to soak the head of the stock and leak all over the billiard cloth and leather case.

How about this idea: Countersink the screw with a hex drive so you can actually get enough torque on it so the screw stays put, and then thread the countersink for a plug screw.

You could then index the plug screw along the axis of your choice, be it compass, GPS, or "seaman's eye".

"The price of good shotgunnery is constant practice" - Fred Kimble