I love my M14, but this is a perfect example of what some people have said. I have a Norinco M14 with factory barrel, Sadlak spring guide and Wolff Spring, EBR stock and the best group I got was 1.75MOA.
Not sure if I want to throw another $6-7k just to chase that 0.25MOA. I've sort of accepted it for what it is and I still like it, but it probably won't be the first thing I grab if I want to shoot groups.
If you're looking for a local guy that knows his way around M14s, I hear there's a guy that works at DVC Indoor shooting range.
I have never see someone get .25 MOA with M14 , even gold plated one!