I have only used it on 22 rfs on moderately heavy rifles.   It is very strong.  You could easily pick the rifle straight up by the scope if you dared.   However mishandling and giving a sideways bump could knock a base loose--however is was an easy fix, reglue and let cure. I had it happen once or twice and I only missed one relay while it cured.    
There are also very high grade specialty epoxies that might work, however that is another complex topic  

I suspect that a sharp recoiling rifle and a heavy scope with only standard target blocks glued to the barrel might be a problem.   Moderating the situation with a longer (more sq inches) of glue contact area would help---say a rib rather than just two scope blocks, as would a lighter mass scope and or a heavier rifle (less recoil).  A rib would also permit the supplemental use of tape.   OR a hose clamp if you really want to mess with folks heads

The project I have "in the mill" is an old 9.5x47R (= a BP 37-55) open-sight Swiss stalker I want to use as a bench rifle. 
I'm thinking of making a dovetail block that will fit the small rear open sight slot flush with the barrel top flt. Then drill/tap/screwing a long rib-block to the filler block in addition to gluing it to the barrel.
  While the small dovetailed block would not be enough support on its own, combined with the glue it should work.  And the screwed block should help support the glue to avoid light casual lateral impact from breaking the glue bond.  I will also consider a strip, or maybe two if I'm feeling conservative, of fibreglass filament reinforced strapping tape

For thoughs that need a BV 20 moved back, this is a solution.

Frank