Hey Mark whiz,I can't speak for all makes of scopes.I bought a Leupold VarXII. Before mounting it on my Ruger Inline I contacted Leupold. I asked if there would be any damage to the scope if it was used on a muzzleloader. The reply was it will not hurt the scope in anyway. I know a air rifle will ruin one.According to Leupold the recoil from a BP gun will not harm it.I know my friends who have mounted scopes on their ML's. They have all used regular rifle scopes and hasn't had any problems.Leupold also said the same as 1950Kid said. The only difference is the parralax.Ricky..... Knight has scope mounts for their rifles.Check shooters supply catalogs and save money buying them. Ruger Redhawk