Years ago, I picked up a B&D Workmate "Hobbycrafter" vice and it is the handiest thing since pocets on shirts for gun cleaning. Placed on end of my loading bench, rifle stock can be firmly (but gently) clamped in the rubber jaws and the ball shaped base allows tipping rifle muzzle down over the waste basket allowing patches/solvents to fall into the wb.
At the same time found a small bench top B&D Workmate which is mounted on the other end fo bench and secures guns a bit more securely in wooden jaws for more serious work.
Unfortunately, I don't think either fixtures are still available.
Regards,
hm