Apart from the different sized bolt head and magazine cut-out, what is the difference between the regular Savage magnum action and the action used for the 338 LM, if any? Does the latter have a larger diameter (i.e. 1.40" vs 1.35") or heat treated differently to accept the greater bolt thrust from the Lapua cartridge?

The reason I ask is that, in the past, it seems that every expert was advising against using the regular 110 mag action for the 338 LM round. Now Savage is producing at least 3 rifles in that caliber. Am I missing something?