My SIL has a Savage 270 Winchester with a 20" barrel. I don't reload for this caliber, since he does not shoot it much and there are many good factory loads for it. This rifle is very accurate with just about any factory load I've shot thru it. One of the factory loads is the Federal Premium load with the Barnes 110 gr TTSX bullet. The MV (in summertime which is the only time I've thus far shot over the chronograph) was only 70 fps less than factory claims (ie, 3,330 fps actual MV vs 3,400 fps factory stated MV). My SIL just back from Iraq and he has yet to take any deer with this rifle. Hopefully, that will change this coming deer season.
If your concern is loss of velocity due to the shorter barrel, well, yes, there will be some loss of velocity. However, it won't amount to a hill of beans at any sane distance within which deer (or other game animals) are typically shot. Based on what you've stated, it doesn't sound like long range shooting is one of your primary goals for which a longer barrel would be beneficial. FWIW, long range to me is 300 yards or more, though this definition will change with each individual. One other thing, the muzzle blast will be louder but I've not found this to be a problem at all, since I always use electronic ear muffs for shooting at the range and when I'm hunting. Since I hunt from tree stands, the use of electronic ear muffs poses no problem for me. YMMV.
Though I've never owned a 30-06 (I know, that's heresy), I'd say the same is true as for the 270. I'm sure someone with more experience will chime in.
Good luck and good hunting.