it got nerfed a while back and meanwhile after so many patches it fell behind alot more. what are the stats of the m4c btw?
https://docs.google.com/spreadsheets/d/1H5z6szCfhmAAnDprmgwLzc-viZg4HPhKZshNLErvnck/edit#gid=1638665511
Assuming they're accurate. Check the "Object AOE profiles" tab for the tank's scatter/aoe stats.