Absolutely cheating.  He had a good round here http://battlelog.battlefield.com/bf4/battlereport/show/1/872212396061124544/821827215/ which is in the realm of possibility.  Then he has a round of 127-34 IMMEDIATELY after  http://battlelog.battlefield.com/bf4/battlereport/show/1/872220428283307968/821827215/ which is absolutely impossible.  This prompted him to be specced by a couple of us.  Soon as he was being specced (he of course knows he is being specced) he became inept (spec starts at about 2:00 in) https://www.youtube.com/watch?v=3_IamsaGrMc.  Of course he does nothing and just trolls chat and messes around and has this round http://battlelog.battlefield.com/bf4/battlereport/show/1/872229306920232896/821827215/.  He was subsequently banned from that server.  Up to that point his overall accuracy was around 6% which is terrible.  Absolutely improbable that he could ever go 127-34 on a 60% locker server.

Had to do some math for this, but from the Battle Report you linked me, he did approximately 57.7% damage with the MG4.  That's beyond the listed damage value for the weapon in Hardcore mode.

Banned.