RE: Good long-range deer calibers.
I will agree that everyone's definition of a "long" shot is different, so here is my humble opinion. I had a 30-06 for a number of years, and it was a great gun to 300 yards, after that you had better know your ballistics tables real well. I switched to an A-Bolt 7mm Rem Mag, and I havenn't looked back yet. 300 yard shots with that rifle are chip shots, my longest shot on a deer was 527 yards, that deer ran about 60 yards and piled up. Bullet was a handloaded Hornady 139gr SST. Only complaint I have with the rifle is the 26" barrel for getting in and out of stands/vehicles/etc. If I was to do it over and buy a different 7mm, I would take a real close look at the Tikka T3s, as I have one in 243 and it is a tack driver.
Like the others have stated, just because you are shooting a bigger gun, doesn't mean there will be less tracking, 1 shot kills, etc. My 243 made a 512 yard shot on a muley in Nebraksa last year, the deer tumbled 30 yards (it was running when I shot it).
I'm not claiming to be an expert shot, I am just trying to point out if you practice and get to know your gun, long shots and 1 shot kills are feasible everytime you squeeze the trigger.