If you are going to kill people and blow things up, at least you can do it so the rest of the living can have a pollution free Earth. It seems the US military has been developing “green” ammunition for some time now.
In 2007, responding to reports from the field that current rounds weren't deadly enough, the Army jump-started efforts to make a more lethal round that was also environmentally friendly.
Link
I wish they had specified the grain weight of the round; is it similar to the 5.56 Nato MK262 Mod1 77gr (Black Hills) long range SPR round? If so, the extra grain weight coupled with the higher velocity might account for most of that performance.
I hope the poster of this blog post sees the irony - or the absurdity - of this statement. Although I doubt it considering how he seems to be some gun/army/weapons aficionado.