I agree about the "cost money" part, but the Springfield M1A SOCOM-16 is fairly light, and very handy and quite pleasant to shoot (with ear protection). With a 1x electronic sight, it's a plinker on steroids. I have complete confidence in mine up to 300 yards. After that, my eyes need help before my M1A does. The rifle is willing, but the eyes are weak.
Effective fire on a point target at 800 yards, as opposed to mass volley fire, requires a serious rifle with a serious scope, and some serious practice. You can probably save $400 by going with a quality bolt action, rather than semiauto, but you still need the same scope, and the same amount of practice.
Shots at 800 yards, outside of mountains and open plains, are few and far between. It's the "big leagues" of rifle shooting, and you have to gear up for it appropriately.
I was going to get a SOCOM. But they are pricey, some heavy, and expensive to feed. I had a Colt AR, mags and ammo. So I spent my “stimulus” on a DPMS shorty. Nice and light, uses stuff I already have. EOtech sight and it is good for urban areas.
I agree, those long shots are the big leagues. And somewhat rare. For those, my bolt guns. But the ARs are fine out to 300 yds for anti personnel. Regardless, I still want a SOCOM. FRegards.