6.5 Creedmoor will be fine on warthog. I'm taking my 6.5x55 CZ 550 FS to Limpopo in three weeks - planning to use it on impala, klippy, duiker, and mountain reedbuck. Also will have my 35 Whelen along for nyala, warthog, and black wildebeest. I discussed with my outfitter and he was very comfortable with the 6.5 up to impala/springbuck. I'm planning to use my 35 Whelen for my warthog, but if a good old gnarly pig steps in front of me with my 6.5x55 I wouldn't hesitate to take him with that caliber.
Still futzing with my 6.5x55 load *way* to late in the game - really want to shoot 140g Aframes but can't find a load this rifle really likes. All just outside an inch to 1.5". One more range trip this weekend and I have to settle on a recipe and load up 40 pills to take pretty quickly.
Back on topic, I won a raffle for a 6.5 Creedmoor Mauser M18 at the Atlanta SCI banquet in March. Wasn't impressed with the M18 at all so I traded it (and cash, obviously) for a Christensen Mesa in 6.5 Creedmoor. That rifle, just like my Christensen in 300WM is a tack driver and is not picky about what you feed it. Shot factory Barnes 127 LRX, Federal 140 AB, and cheap American Whitetail 129 Interlocks inside MOA and the rifle isn't even broken in yet. The LRX and AB factory loads were *well* inside an inch at 100 yards.
The 130 Scirocco in Norma's American PH line was a little outside an inch. Ordered a box of factory 143 ELD-X to try next. I'm strongly leaning towards the Federal 140g AB as my go to, since I like heavy for caliber bullents and Accubond's performance on game.
If all my paperwork wasn't already done and submitted for the CZ 6.5x55 I'd be taking this Christensen 6.5 Creedmoor instead!