Don't think I'd want to try running a .338 Lapua on an older standard belted magnum action (small shank barrel and older magnum bolt head with thinner lugs). Savage uses a specific Heavy Magnum bolt head for the .338 Lapua, which IIRC also requires a unique front baffle and firing pin assembly to match.

Even properly configured with the correct parts, the .338 Lapua is really too much cartridge for the Savage action design. Several have come through Fred's shop with very low round counts and were already exhibiting obvious lug setback. There's a reason most all of the custom action manufacturers have a special larger action just for the .338 Lapua Mag and similarly sized cartridges.