My RUGER PC chassis carbine (16"barrel) shoots ANY ammo. That's one of the PCs attributes. CCI 129 gr. FMJ seems to be the most accurate so far.
I've upgraded my PC with M*CARBO machined and hardened extractor, bolt pins and bolt recoil pad and a TANDEMKROSS bolt recoil spring. Outside I've added an M*CARBO raised mag release button and mini brake. Most of the rest of the exterior upgrades are mostly MAGPUL parts except for a folding stock "knuckle".
A HOLOSUN AEMS circle/dot sight sits on the barrel's Pic rail. It is, IMHO, the best "red dot" sight for a PCC.