Not necessarily it could've jammed the turret traverse. I would have just dropped a RKG grenade as it would have been a better choice. I had one go through one of my MRAPs in Iraq and went through the roof, side, ballistic glass, and out the floor.
I would argue that Sub .50 Cal Rifles are useless for anything but Niche Roles. The USCG investigated the .50 cal Beowulf and the .499 LWRC and found them not up to task.