THERES a few really nice rifles posted in this thread, but I would not get all that concerned with the caliber used,If you like it and its accurate, and feels good in your hands, its almost a sure deal it will work out fine!
I try almost all my new rifles out on the local white tail, as were allowed, a deer a day in many areas,here in florida,and the seasons a couple months long if you add up archery,front loader and rifle seasons,, now I like venison, if the freezer gets a bit empty, Ive used a 44 mag with 310 grain lee cast bullets ,a 257 roberts, with 100 grain speer and hornady bullets,a 257 wby with 120 grain Remington bullets, a 270 win, with 150 speer, and hornady bullets , a 30/06 with 200 grain speer bullets,and 180 grain hornadys a 358 win with 250 speer bullets,a 375 H&H with 235 grain and 270 grain, jacketed bullets, a 45/70 with hard cast,and 405 remington,soft points, a 458 win with 450 grain hard cast, a 62 caliber round ball from a muzzle loader, and a 32" 700 grain ,arrow with a twin blade MUZZY broad head from my 84lb 32" draw compound bow.

so , my conclusion, is that what you use is almost meaningless,IF you can shoot it accurately and know the games anatomy, simply because they ALL WORKED JUST FINE.
YEAH, lately I grab my 44 mag marlin or my 358 win BLR for most whitetail hunts but I have little doubt that you could use something like a 223 rem if you could place shots well (many of my friends do that regularly)
one of my hunting buddies, (AL) who has been rather successful had a 303 enfield jungle carbine for several decades.
[Linked Image]

He had used that carbine for many years to hunt deer very successfully, he bragged for years how his old 303 smacked the CRAP, out of our Florida deer that rarely go more than 120lbs.
now keep in mind, the ranges where he hunts seldom exceed 40 yards and 50 yards is a rare long shot, most shots are taken at under 40 yards , in very thick brush. hes killed dozens of deer with that 303,jungle carbine for several decades ,but he had never been to an actual rifle range, he had always set up a beer or coke can on a dirt embankment, backed off about 20-to-25 paces and tried a shot from about 35-40 yards and having hit the coke can, felt 100% sure the rifle was still correctly sighted in, like it had been for years, he had me load the ammo to match factory velocity's ,
http://www.speer-bullets.com/ballistics/detail.aspx?id=107 with these 180 grain soft points, http://www.handloads.com/loaddata/d...amp;Weight=All&type=Rifle&Source
over 45 grains of WW760,In my enfield it shot 2.5" 100 yard groups with iron sites off the bench,
but I totally ruined his confidence in that rifle when I made the bad mistake of taking him to a local range, for thirty years or more he had simply placed an old bottle or can on a hillside, backed off 30 or so long paces and fired at the target, with a high probability of a hit! occasionally he needed two shots to hit the beer can, but that was rare.....well I took him to the range and all his 50 yard targets had nice reasonably tight groups using the issue iron sights that measured about 3" in spread,the problem was most of the holes in the paper were key-holed, or profiles of the bullets ,it was obvious some, even most, bullets went thru at an angle or even side ways, he was very upset.....we pointed out that he had been very successful with the gun, even if it did tend to allow the bullets to tumble, end over end which the paper target clearly showed..
so far hes not been able to locate a replacement 303 British, caliber jungle carbine barrel for his carbine, and careful inspection shows the rifling is all but worn away, in fact it is so shallow, and the bores so eroded, its basically useless!
improper cleaning,improper storage,general abuse, improper solvents and corrosive primer ammo use by previous owners, long before he bought the rifle at a yard sake 30 plus years ago, sure didn,t help either.
so again Id say what you use on white tail deer is not as important as your ability to place shots consistently on the intended target