Apparently absence of recoil is justified by design http://feedback.arma3.com/view.php?id=15255

However if you tried to use it, in full auto it lays bullets in the same spot with a Swiss watch precision. I don't think any tripod is capable of reducing recoil to 0. There should be at least some recoil for realism, not to mention the overpowered aspect of .50 cal with no recoil whatsoever.