I've got both, and tend to carry the .308 more than the .30-30, due more to sighting system rather than the distance potential of the cartridge. As a matter of fact, I've killed a deer at a longer distance with the .30-30 than I have with the .308, but would have preferred the latter. Nonetheless, familiarity with the rifle and it's trajectory allowed me to make the shot.
The .308 is a Ruger Hawkeye All-Weather with a Leupold scope, the .30-30 is a Winchester M94 (non-AE) with a Williams FP rear sight and Marble's front sight.
Where and how I hunt, most shots will be within 100 yards, typically half of that, so either one is quite usable.
I just got back from the range sighting in my .45-70 that I had just installed a Leupold FX-II 2.5 Ultralight on, and using Speer 300 grain UniCors at 2200 fps, got groups from .970" to just over 1.5" at 100 yards. This bullet, at this speed, closely duplicates a .30-30's trajectory.
The Ruger and the Winchester may be out of a job next year (grin).
