I'm afraid the long term may be to go back to something smaller, lighter with more capacity. I don't really get the 6.8 choice to be frank. The chart in the article really is a head scratcher over .308. The bullets available (from what little I know) don't have nearly the available ballistic coefficient choices of 6mm or 6.5mm projectiles. Seems like a cartridge slightly longer than 45mm with a 6mm or 6.5mm round would make even more sense from a weight and BC perspective and the longer case would help with feeding in a non-constant curve mag (assuming we wanted to stick with drop free rather than rock in).I wonder if the long term idea is to move the M4 inventory (and it's ammo, parts etc) to reserve units, or just give it out to the 'colonial' armies and let them do the mass warfare?