New Army "Caliber Configuration Study"

[stanc]

What does a dismounted patrol need doing, with only the weapons and ammo they can carry on their backs, that can't be done with the combo of 65G ARs and LMGs, and ABGLs?

Ah, but that is a considerably different question than that of the scenario in your previous post.

If we assume that the significantly lighter, lead-free bullets would provide 7.62 range, and that a belt-fed Grendel LMG is actually doable, then I think such a weapons mix would be viable for foot-mobile infantry. (Although, as LRRPF52 keeps pointing out, the combat endurance of riflemen would be substantially reduced vs 5.56mm carbines, which would necessitate more frequent resupply.)