It's a weird rectangular shaped SMG. It was only seen in one magazine preview, but you won't see pics of it here or on the wiki because there's no scans allowed.
8 strength to use at maximum efficiency. First off, the weapon is pretty heavy, so to shoulder it and hold it steady is difficult for someone who isn't strong anyway. It's meant to be fired from prone position, but since we can't go prone here that's a no go. Also, it has significant recoil. I saw that when they shot it the guy was blasted back by the recoil- I'd imagine that effect is reduced by a higher strength.
But as for the effects of hitting a target, a .50 BMG rifle is powerful, but it's not going to create a vortex of doom that rips people apart. It's not going to kill anyone unless it hits. A .50 BMG bullet flying past your head won't cause it to explode. :laugh:
As for the recoil. I've talked to many people who have fired them, including a cop who was a little messed up by a car hitting him while he was in pursuit, and while some said it had a pretty big recoil, the majority said it wasn't all that bad, atleast not as bad as MGs. I've also seen vids of people shooting .50cals. As for the "vortex of doom" I had heard it and read it from accounts of people, some "claim" to have seen it first hand and say that, "a large, high velocity round creates a deadly vortex around itself as it picks up speed." or that a a .50 cal round has enough force to break someones neck if it passes. Though after reading other topics on it, I don't believe it can either anymore. And although it may not kill from missing, it would in some cases rip someone literally in half if it hit, or just make a huge un-recognizable mess.