My mantra has always been, "ammo first then gun". If you can't pick up the ammo at a Walmart, you'll never get if when the shtf. But with this rifle, I plan on working on precision & accuracy at distance. If I build/rebuild my skill, I'll move up in ammo & rifle.
You’ll come closer to picking up .280 Rem at Wally’s than you will 6.5 Creedmoor.
As far a ballistics go, you should check the stats on the .280 Rem pushing 140 gr bullets @ 3100 fps.