Loctite #242 blue - medium strength : LOCTITE THREAD LOCKER ADHESIVE | Sinclair Intl

Most gunsmiths use LOCTITE 242 blue threadlock adhesive on the base screws when they are mounting scopes. This is a medium strength adhesive that can be disassembled with normal tools. We use red LOCTITE 271 when we assemble rest tops to rest posts or other assemblies that we don’t want to come apart. Loctite 271 requires heat or special tools to disassemble parts. Both cure completely in 24 hours. 6 ml tube.

Sinclair, Issue:4A, Page:205
Sinclair, Issue:4A, Page:250