I do agree with you but because started nitpicking I'll just have to say that grenades by definition are not propelled at all. Rockets are, and that's why they are called rocketsLukeValantine said:Just wanted to point out how insane this statement was. Rocket propelled grenades by their very nature are a hell lot slower then rifle bullets, and no matter of sci-fi nonsense will change the fact.
I haven't studied the Space Marine fluff too intensely but the HH series speak nothing of those links from their visor to their guns. Might be post-heresy invention, though