I think they are making a big mistake going with HK it will bite them in the ass later with the high cost of replacement parts, and the contracting with HK (Germans)... The Marines will not be able to deviate from the contract once signed. (nice guns poor customer relations) this is my opinion of course I expect flames from the HK lovers.
If they wanted lighter they should have just gotten a belt feed conversion for the
M16
http://www.dndguns.com/shrike.htm.
If you want dependable M240L
http://peosoldier.armylive.dodlive.m...m-machine-gun/