Best answer I can give is one I found on google.
I'm sure there is someone here on the boards more qualified, but hopefully this will get you started.
308Win. with 150gr. bullet: Max. range = 4,470yds.
Muzzle vel.: 2820fps
Angle of Departure: 35.2 deg.
Source: Lyman's Guide to Big Game Cartridges & Rifles, pg.146/147.
Note: 1,760yds. in a mile.
Best of luck with the range. I'd be thrilled if someone opened up anything more than a hundred yard range around here. Shoot, I'd be out there pounding poles and moving dirt with em.