it kicks like a 12ga shotgun. you see that muzzlebreak on the front of the barrel? ever wonder why they put such a massive one on taht rifle? it directs most of the gas to both sides of the shooter, and lowers the felt recoil A LOT.
it doesn't kick bad. it just sucks being the spotter
i've shot a .50BMG rifle before, it sucks much more standing next to it.