I own many guns in a wide variety of calibers, 223 to 45-70. 30-30 to .338. If I had to choose one gun I would get the 30-06. Best selection of bullets of any caliber made. Close range White tail, down load and use the 150, or 170gr flat nose bullet designed for the slow speeds of the 30-30. Fast expansion for low velocity, little damage. For longer ranges, 100 to 600 yards use a 165 grain boat tail. I'm partial to head shots, and with my 06 they are easy to make. I carry an 06 from October to March, and have shot everything from Moose to foxes. I've even used it to shoot the heads off Grouse and Ptarmigen (at close range). I used my Handi 30-06 to kill a Moose the 12th of Nov. One shot in the forehead right above the eyes, with a 180gr Nosler Partition, from 250 yards. I also carry the 06 when I go to Tennessee and Texas for Whitetail each year. Ranges can be from 20 yards out. In west Texas I often make 300 and 400 yard shots. My Dad and brothers used to complain that I was overgunned for Tennessee whitetails, they all carry 30-30s. Five years ago we were sitting on my uncles carport drinking tea when we saw a doe walk out into a clearing on the hillside across the hollow. The doe kept stopping and looking back as she crossed the clearing. My Dad said there was probably a buck following her. I went to the truck and got out my 06. I laid it across the hood of the truck, we quessed it to be about 600 yards. When the busk walked out I took my first shot, the buck froze. I had shot too high. My second shot he stumbled and took off running. He ran into a clump of ceders, but did not come out. We sat down and finished our tea, then after about 30 minutes we started over there. We found him in the ceders. I had hit him a little high taking out the far lung. The only meat loss was rib meat, about the size of a silver doller on the entry side, and about the size of a baseball on the exit side. I had hit a rib on the exit side. I was using a Sierra 165gr spier point, boat tail bullet in front of IMR 3031.
One good reason to carry the 30-06, is I sometimes get invitations to go hunting with people I meet during my travels. back at their homes. A few years ago while hunting Mulies in New Mexico with my in-laws, I met a guy from Montana who invited me to stop in at his place on my way back to Alaska to hunt Elk. While there his brother came up from Wyoming and invited me to go with him for antelope. The 06 was up to it, scored on both.