Well the US Army might want to be green but why not get an effective round into combat use now so allied troops and their own have a far better chance of success in a gun fight. This would include less casualties to our own. They can keep working on the green ammo after they get effective ammo in the field.

Agreed. bring back the 7.62X51. Nothing wrong with the old SLR etc. Some may complain about the weight but once it starts to show how effective it is at 0 to 600+ meters not too many will complain.

If they do not want to go to the expense of re equiping and traing with a new firearm then go to the 6.8SPC or 6.5Grendel. Same weapon just replace the upper, barrel and mag follower. Not as effective as a 308 but more than a 5.56. Just my opinion.