They are actually two different games. You can play the Horus Heresy, which is what people mean when they say "30K" in reference to the time setting and the rules, army lists, and scenarios as laid out in the Forgeworld Horus Heresy rule books. You can also decide to play "40k," normal Warhammer 40,000, using the rules as dictated in the Warhammer 40,000 rulebook from Games Workshop. They are two distinct games, set within the same lore universe.
To use models and rules from 30k in 40k would be quite a bit much, since the rules and special rules for units in 30K are inherently stronger and more powerful than most basic rules in 40K.[/QUOTE]
People Saying that playing 40k and 30k are two different games don't seem to realise that that 30k USES 40k rules. While I agree that 30k armies are meant to play better against other 30k armies, there is no functional reason why 30k armies can't play against 40k armies either, just as long as you use the normal 40k force org charts for your 30k lists. When I eventually get my 30k list built up, I'm going to play it against other 40k lists.
On the main note of this topic, the tournament is supposed to be unbound right? So anything goes right? There is no offical ban list in this tournament right? On that point alone there is no reason why you can't Ferrus Manus and his Iron Hands to it.