I voted for AR-10, I really like my dpms, all the fun of an AR without the mouse round, a close second would be a M-1 Garand, pretty much the original all purpose semi auto rifle
one caliber will not do it... a min of two rifles needed + a pistol
can't help but think in terms of survival...
first rifle would have to be a .22LR... my choice would be a CZ 452 bolt and several thousand rounds of .22LR.
second would be a larger caliber ... .270 or .30 bolt ... my Weatherby .270 has taken down the most vittles... but logical choice has to use .308 or 30.06 due to ammo.
I'll change my vote to Kel-Tec RFB 18" in .260 Rem. But still a lot to be said for a turnbolt, where lightness and reliability in all environments is at a premium.
I have been welded to the AR-15/ M-16/ M-4 family since I fired the first one many moons back. I like the round and the choices I have in it. I like the platform. I recently added a Tac-2 "Discreet carry kit" to my Bushmaster and it has a takedown barrel and carries in a briefcase with 2, 30 rd mags. There are so may iterations to this system that almost anyone can build what they want to on a basic upper/lower/ barrel.
Definitely an 18" M1A/M14. Those suckers are accurate for several hundred yards, it will be compact for maneuvering, and it has the firepower to stop ANY breathing animal in North America... unless maybe an elephant breaks out of the zoo
AR-10.
With a 20" heavy (not bull) barrel and flat top with scope you can take anything in North America out to 200 to 300 yds. Deer out to 500. The AR platform provides ample accuracy as well.
The poll is about all around rifle so of course I'd use my buckmark or .38 revolver with target loads for small game.
SD/HD? In 10 seconds you can swap out the upper to a quick handling 16" tapered barrel with carry handle for up close and personal. One hit mid torso with a 150gr (125gr available also) hollow point...game over.
No other weapon on the poll list has this kind of veratility.
Ammo for it? Everywhere you look. And right now steel case .308 is running a whopping (sarcasm intended) $4.00 a box more than 7.62x39. Sell your AK/AR and you can buy a boat load of it.
Accuracy? You have to spend a good deal of money on an M1A to get under an inch at 100yds. My Armalite has that out of the box.
As far as a "one rifle do it all" (a scenario I'll never purposely place myself in, by the way) nothing comes close to the AR-10 platform.
I still havent decided what its going to be, the AR has quite a following in the poll. I have had several of the rifles in the poll and foolishly got rid of them