.338 mmg

[Tony Williams]

I suppose a bullet weight of 300 grains vs. 147gr for 7.62 NATO at least doubles the ammo weight. This really says "vehicle-mounted only" to me.

Actually it isn't quite double - the round weighs 700 grains compared with around 370-380 grains for 7.62mm.

A LWMMG plus enough ammo for one minute's continuous firing (500 rounds) weighs just under 105 lbs, whereas an M240 plus one minute (800 rounds) weighs 100 lbs. So from that perspective, there isn't much in it. It isn't too heavy to be carried in those circumstances in which the ability to reach out to well over 1000m is a real advantage.

In an ideal world we would have something like the Grendel as the standard rifle/LMG round carried by dismounted infantry, backed up by something like the 338NM MG in a support role, perhaps at platoon level.