new old stock Remington barrels

I bought a bindle(a bunch) of new barrels included are some Remington shotgun barrels from looks of packaging I'm guessing they are about 20 or more years old.
there is one that maybe someone can offer me guidance on. its a 12 gauge cantilever slug barrel for an 11-87 and the cantilever for mounting scope is off center. since I'm pretty sure this stuff is no longer covered under any warranty
I removed the fasteners and pulled off the cantilever to find that the slot it fits in on the barrel is filled with some sort of adhesive. with adhesive removed there is plenty of room for adjustment
I'm going to scrape it all out and reset the piece straight. what kind of adheisive should be in there?

If it was me doing it, I would use something like Accraglas Gel. JB weld would probably work also.

Depends if the adhesive will be seen or not. It sounds like there are also screws holding the mount on?

Robert

I've glued a lot of open sights on with JB weld