So, we've all got Space Marine armies and now we all want some grav guns. What shall we do? I don't need to buy any more tactical marines, and that box only contains one gun and one pistol anyway.
Bits sites have already started selling outs and are charging upwards of £5 for each gun, so that's not an option. Here's what it looks like - sort of like a stubby round plasma gun.
Grav guns can probably be represented by their ancestor, the Graviton Gun.
At the moment, though, this only available in the Forge World Boarding Assault upgrade kit - £18 for one gun (and a load of other stuff) - or as part of the Legion Breacher Squad - £32 for five guys and one graviton gun!
Of course, a classic Graviton Gun looks quite a lot like the classic (heresy-era) flamer, and forgeworld sells ten of those for £11 - wack some nobbles on it and remove the canister and they might work -
http://www.forgeworld.co.uk/Warhammer-40000/Space_Marines/Space_Marine-Infantry-and-Accessories/LEGION_FLAMER_SET.html
Third party, Anvil industry also sells a nozzled 'acid gun' that could work well - £1.50 each with a flamer option too.
http://www.anvilindustry.co.uk/index.php?route=product/product&path=60_104&product_id=231
Any other suggestions??