New Army "Caliber Configuration Study"

[JASmith]

I was referring to it's terminal performance on vehicles and light armor.

I think we both are.

Yes, given the same impact velocity, the longer, heavier, bigger diameter bullet having greater terminal performance is almost a no-brainer. What velocities do they arrive at?

If the .338 has a significantly greater impact velocity at range, then answering the question is more challenging.

Further, as with the 7.62 replacement discussion, there will be the question of value-added by going with lighter ammunition (greater round count per pound) and weapons versus improving the terminal performance of the existing cartridge.