My Remington 700 SPS-V, bought in 2009, was hardly a shooter and rarely went below 1.5" at 100yds. Granted it was a 308, not 300WM, but what made it a poor shooter was what would apply across the board. I transplanted it to a B&C stock but saw moderate improvement, with groups measuring maybe 1-1.25" at 100yds. When I measured the throat to better reload for it, my measured OAL was in the 2.9" range for the 168 AMAX. Waaayyyy long. I took it to the local gunsmith and had him set the barrel back, but in doing so, he had to set it back almost 1/4" due to the fact that the chamber was almost .006" out of concentric with the bore. Pretty obvious whoever chambered it didn't indicate off the bore when he chucked it up for chambering. Once it was re-chambered, true to the bore, and with an M852/FGMM reamer, it shot sub-MOA easily.
If I am going to get another R700, it will be an older one ... oh wait, just did that with a Rem 721 action in 270. Sent it to RW Snyder and he put a Krieger 1:10 heavy Palma on it and chambered it for 300WM.