I have a 2X8 Pistol Scope on my XP-100 and a 2.5x8 on my Thompson Contender. (Actually have three of those, one on my .221 Fireball Barrel, one on my .22 Jet Barrel and one on my .224 Barrel. Unless you are on a good rest or reall have your tripod on something sturdy, I have found higher magnification to be a problem.
All of these set ups hold nice groups out to more than 250 yards from a bench.
Bob