Rosin? I've always used the traditional powdered rosin, no gluing, scuffing (on the scope tube from abrasive grit), dimension change. Dissolves in alcohol so it comes off easily. But then I've never dealt with recoil much over .30-'06 levels.
I've got a BIG jag of that powdered
ROSIN , and would be tickled to send some to any that require a pinch . A little goes a long ways, and Brownells useta' ship it in a HUGE box.
Guys, if you throw some Coniferous
ROSIN into a little de-natured Alky, you've GOT "Indian Head Shellac."
I've reduced it with common turps, too. NICE to be able to paint it on, and just THE thing for making an adjustment screw "sticky" without locking it up solid. The set trigger screw on any number of historic arms, and replicas thereof on example.
GTC