Long range for me is defined as accurate out to 1000 yards. Here is my precision rifle ....Rem SPS TAC..AICS chassis...Nightforce 5.5 X 22 X 50 NXS...308
Barska scopes are junk. Chinese made and inferior glass, with plastic internals. Good glass is crucial at LR at high magnification. The critical item for long range shooting is a quality optic. The ability to range the target with mil-dot or MOAR reticles, in a repeatable scope is critical. the '06 is a good caliber, but not ideal for this application.
The second item is a quality stock, properly bedded. Action screws torqued to spec.
Quality match grade or handloaded ammo is a must as well. Crap ammo in a precision rifle platform just doesn't make sense.
Go to snipershide.com and read up...you'll get plenty of info on the long range game...it's where the big dogs play
If you buy the cheap gear, this will just add up to frustration in the form of missing by a mile at ranges over 800 yds. You won't have much "fun". Save and be patient until you can afford quality mounts and a decent scope. Buy once...cry once.
The Remington 700 is an excellent platform