Re: savage 12fvss improvements?
Reliable optics, some diligent load developmen, and shoot the heck out of it.
My buddy and I used a 112BVSS (long action version of the same rifle) .308 as a standby loaner for newbies. It perforaed flawlessly for two 1000yd F Class seasons, shooting to the potential of all comers, including some well experinced F Class shooters.
IMHO the best way to improve its accuracy is to improve your own. If you ever find it holding you back, replace the barrel with a longer L-W .260 1:8" barrel and really see what LR precision shooting can be.
That rifle was the one rifle I could reliably trust to never be 'the problem'. Alas, I never actually owned it and had to oblige when the actual owner wanted it back. I still miss that rifle.
Greg