My dad has a rem 700 25-06. He shoots factory rem ammo. He shoots a 3" group @ 500. Quite impressive... for factory rounds.
If he shoots 3" groups at 500 yards with a stock Remington 700 25/06 with factory ammo,he's got to be one of the best marksmen in the world.
There aren't that many guy's that shoot custom built benchrest rifles shooting custom handloads that can shoot that good. That's just a little over 1/2 MOA for that distance!
He better start entering a bunch of shooting competitions with that rifle,and ammo.
I'm not saying that it couldn't happen,but I would have to see it done to believe it.