My M98's in 8mm Mauser, with 23.4" barrels easily dis 2,400fps with 225gr.Speer bullets and N204 powder. This means they should do the same speeds with Reloader #19 or #22, which ever is equivalent or the same & likely several other modern powders as well.
: The .318WR and 8mmMauser are so close as to not really show any difference ballistically that I can see. the 8mm certainly has the advantage in bullet availability and selection unless you're into 'drawing' .338" bullets if you have to.
: The 8mm/06 is an easy conversion anyone can do at home and since the shoduler is being moved forward, the tube doesn't even have to be removed and your easily loaded ammo being used for a headspace gauge.