I hear you about wanting to start with a .223 for some of the same the reasons you sighted. I also restarted shooting last year and bought a pre-owned .223 in a 700 Remington BDL. It is a handsome rifle, as well. I put a very good Nikon 6-20X 50MM scope on it and I've really enjoyed shooting this set up. The 700 BDL however has a 1 in 12 twist so you won't be able to push the heavier bullets. I max out at about 62 grainers. I find the 55 grainers and 62 grain bullets shoot just about the same in my rifle. The other drawback is NO CLIP with this rifle. You feed the cartridges one by one into the spring tensioned feed chamber in the rifle, and although it holds 5 rounds, it is a bit of a pain to load especially in the cold or in low light.
It really shoots well, groups well, and it shoots like a lazer (consistent over 100 to 300 yards). I have yet to shoot it out to 500 yards.
I shot the M16 in the corp and found it quite accurate. Are you mostly shooting PAPER? Or will you hunt game? If you are mostly shooting paper and maybe a ground hog or two I would say a 700 BDL or straight 700 Remington in 223 caliber would work for you up to 500 yards, although if you plan on HUNTING most consistency and deadliness will probably occur 300 yards or closer. But that depends more on the shooter and less on the rifle. If you want to go farther than 500 yards then your 30-06 should work out for you.
I am setting up a range on my new land out to about 450 yards which is all I can get out of the topography and trees, but I hope to learn more about what my .223 can really do... there are also FOXES so I think I may learn what its deadly distance is as well.... /ubbthreads/images/graemlins/wink.gif