This guy has a gas powered assault cannon thing. The ammo is contained in the drum on the front.
I love this one, the grot on his back is removing bullets from the feed and dropping them into the ammo loader!
I can't stand the look of the shoulder mounted deff guns, which is a shame because the unit is such a nice thing to field in an army. Instead I always wanted them to be hulking about massive miniguns of some sort, which is why I bought the maxmini miniguns they recently added to their web store. Unfortunately they are only as large as an ork boyz shoota and are more in keeping with a human wielder. I bought a box of lootas anyway and began hacking up the bits and repositioning them to suit my initial idea. I am really pleased with the way the first two have come out. It just takes some patience, limb repositioning and greenstuff but I guess that's all part of the fun! Just another eight to go.
Also here is my finished dread. He doesn't have a name yet.