All the 6.8 is a good compromise between .223 and .308. Buying a new personal battle weapon I'd go with the 7.62 NATO round every time.
So we should reissue the M14, or a newer version, as a "personal battle weapon"?
Or the M60 which I lugged around in Viet Nam? 23 lbs + 7 lbs per 100 ammo. The M240 is even heavier.
1969 9th Infantry Div. 2/60 Long An province.
I spent nights on ambush patrols wishing for an M60 variant that fired the 5.56 round. Lugging 300-400 rounds, and every other grunt with a belt of 100 got real tired very quickly. I put it in the "suggestion box". When the SAW came out, I should have demanded a royalty. 1/2 the weight per round, and 2/3 the weight of the excellent M60 is very appealing to a 11Bravo.
No stopping power? Lots of dead VC would not agree.
6.8 is dumb. Now 3 calibers to mess up the supply.