Havocs and Chaos Terminators use them, and I think that's fine. It doesn't make too much sense to me for an unaugmented human to be able to do it, though. They could probably fix it by making an Astartes autocannon with a statline more comparable to a heavy bolter and making the default autocannon a mounted type weapon.<br/><br/>I really they'd given Astartes melee weapons a bunch in the arm when they looked at the weapons table. It just doesn't feel right to me that an Astartes Chainsword has 1 more point of damage and 1 more point of penetration over a non-Astartes chainsword, and that Astartes power sword has 1 more point of damage over its non-Astartes counterpart. Sure Astartes get unnatural strength give them a bit more punch and their power armour's augmentation, but they make such a big deal about how Astartes weaponry is just so much bigger and badder than weaponry designed for humans that it seems like undue hyperbole when you compare melee weapons (with ranged weapons, however, things are rather fitting, though I think the errata still did not go quite far enough in making non-bolter weapons as attractive as they could be, although maybe I just find the reload times unnecessarily punishing in many cases).