Being an experimenter, I looked back in my 48yr deer hunting life ( we didn't have huntable numbers until I was 11, the deer were still recovering from the Screw Worm epidemic, SE Texas) I have used close to 15-17 different calibers in even more rifles. Can't pick a favorite, as I had the priviledge to hunt places from thickets to prairies. Looking back, I's have to say I've shot more deer with standard cased or wildcat 6mm & 7mm (.280) caliber rifles, a few 7mm remmag kills, all bolt guns. A .220 Swift was just awesome on them, and a 30.06 was crowding "magnum territory" on them. For the thick woods, it would have to be 30-30, in either a Mod 94 or Marlin. Good, solid killer on deer and hogs.
As a son of a Great Depression Survivor, I was taught to "not waste any meat", as if we would starve to death over some bloodshot meat! ha. So I learned early on to shoot all hogs behind the ear, and deer through the heart'lung area or head shots. Not enough meat on a East Texas whitetail ribs to fuss with. I found the 30-30 to be excellent for this, but the 30.06 with the 150 CorLokt was just like a 7 Remmag on them. Sure, I've used 300 winmags and 300 RUMs too, but it was trying to get some use out of my elk/plains game rifles is all. I now use a 22-250 Ackley Improved with a 75 Swift Scirocco or 64gr PP on the smaller deer. It is built on a Mod 7 blued action/blued Shilen fast twist (8") 24" barrel w/muzzlebrake ( to see where I hit on prairie dogs and coyotes) with a set trigger and a 4x12 Nikon, all set in a synthetic stock. Pure poison, ha! It just mimics the 220 Swift I used to have. My synthetic stocked, Mod 700 .35 Whelen Ackley is my Mountain rifle, and it is a sure killer on deer too, doesn't bloodshot any meat ( few medium calibers do) but I don't eat every scrap and cuss Hoover either, ha. (My dad sure did)