A couple fellas I know up this way are loading 175gr MK's to right around 2900fps out of their custom .308's using a Rock barrel, Nesieka(sp?) action and a very hot charge of Varget. Don't know all the specs, ie COL and chamber dimensions, but that is what they are getting.
I like velocity as much as the next guy but with all of the
different calibers that are available there is no need to load
over max loads.
If I want more velocity than a saami max load for a .308 win
then I would go to a 3006 or even a 300 mag.
There was a time when all of these options were not available
and guys like P O Ackley moved sholders and reduced taper
to gain powder capacity and up the velocity.
I have owned 1 rifle that was used for 1000yrd matchs that was
over loaded by 3 to 4 grains of 4831 and it was deadly BUT the
price I paid was not worth the problems I dealt with( blown primers,
hard bolt lift,very short brass life,bolt face erosion ,etc.
So be happy with what your 308 will do with out excessive pressures
and if you need more just go with a larger round.
308's are very competitive at a 1000yrds with a 168gr MK.
Velocity is like gas mileage there are claims and there are facts.