Not tried it but have worked with adhesives in past. Loctite Anearobics say Loctitie 638 etc would do the job, as would epoxies and two part acrylics. Not sure whether the principle would work though as the thickness of CF needed to stiffen say a 15mm dia barrel considerably would be quite a lot. The flex in whatever adhesive you used would diminish the outcome I feel, so a metal loaded epoxy may be the answer - but would be a b**ger to get off if you change your mind!
Not sure of the science but wonder how a laminate barrel (which is the direction your are going) would fair with Harmonics etc.
Be interested in what you do and whether it works though!
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