300yds no sweat will stay in the black, with match ammo it can be shot to 600 yrds pretty well, but they really need tweaking at that range to score reliably.
Stuff like receiver bedding, match trigger pull, unitized gas cylinder (secured to front band), medium weight match barrel, national match sights (already installed by Marine Armorer at Camp Perry on this one).
For 1000 yrds, all that and more, including fiberglass stock, double or triple lug receiver attach, heavy match barrel cyrogenically stress relieved (stainless steel, 1 in 10" twist, 6 groove) and a couple other little things.
Fun project, and like any good firearm, it appreciates in value the longer you own it if you take reasonable care of it.
dago