The first four models are now based on a mix of coarse sand and fine slate chips, and primed.
I've used a form of zenithal priming, spraying first with Citadel Chaos Black from all angles, touching up with Imperial Primer in the recesses, then a light spray of Halfords grey primer from high angles. Finally, a light dusting of Citadel Skull White from above. This takes a little time, but is especially useful for metal miniatures since you get great coverage, and it makes small details much easier to see when painting.
I also added two Tech Gangers:
The first has arms from the Empire Knights kit (the Knights of the White Wolf parts, which have cloth on the upper arms, armoured bracers and heavy-duty gauntlets) with a knife from a plastic Necromunda Orlock, and a metal lasgun from a Necromunda conversion pack. The other has an arm and laspistol from the Imperial Guard vehicle crew.
These six models will be my initial painting project for the next few weeks.