Would you consider the century arms c308 to be a precision rifle?

No... MBR

I could not say definitively one way or the other.  I would lean toward the "hell no" side of the options, but shit, I've been surprised before.  Only you (or another experienced marksman in your AO could answer that).  

You want a precision, semi-auto .308?  You will need to go down the LR7.62/AR-10/SR25 patterned rifles route.  More over, you will likely need an aftermarket, quality barrel and good trigger.

The term "precision" has to maintain it's definition.  I know many have their perceptions and versions of what a precision rifle is, but I like to keep it simple: can the rifle shoot half minute or sub half at 100 yards?  If the answer is yes, I believe that is precise enough.  If you ask an F Class fella, he may say half MOA is one lousy standard, and say, "same hole groups" or some shit like that.