I was thinking the exact same thing... also, I've never seen any factory gun come anywhere close to winning tin at an F-class match where consistent .25MOA should win.
For a Factory Gun there is F(M) class. "M" being Manufatured with very few mods. Norm B built a F(O) rifle on a Stevens 200, with a heavy barrel and a BR Stock he managed to win the Mons Club Championship and the Fall Palma here in Ontario on back-to-back weekends. Just goes to show the shooter, barrel and ammo have more to do with winning than the action.