This is interesting

It looks like the Army is seeking ideas about replacing the M16/M4 individual weapons platform. From Military.com:

In late August, the Army issued a solicitation to the arms industry asking companies to submit proposals that would demonstrate "improvements in individual weapon performance in the areas of accuracy and dispersion ... reliability and durability in all environments, modularity and terminal performance."

And in a dramatic gesture that could throw the door wide open to a totally new carbine, the service did not constrain ideas to the current 5.56mm round used in the M4.

Well, they're not asking me, but if they did, I'd tell them to keep most of the M16/M4 package. It's reliable, it's easy to manufacture, it's user-friendly. I'd change the caliber, but that's my personal bias. There's nothing inherently wrong with the current class of 5.56 ammo in an infantry rifle. I'd like to see something in 6mm or larger, but again, that's just my bias.

If the Army wants something more modular, it's hard to get more modular than the AR/M4 package. The whole rifle is held together by two pins and swapping parts is easy.

Hat tip to Ahab.