Judging by the picture the armour seems quite reflexive as metal surfaces. So I'd say it looks like unpainted silverish armour with some light bronze/brass tones here and there (especially the back pack top in the middle of the picture). The silver doesn't seem pure, and I'd choose a warmer tone toward beighe/khaki. perhaps spice it up with some tempered heat bloom effects but toned down and more subtle than the heat bloom effects of the FW IH paint scheme.
I'd probably go for something like this:
- Prime black
- Airbrush a base coat of Vallejo metal color gun metal
- Airbrush a midtone with Vallejo metal color exhaust manifold
- Airbrush highlights with a 1:1 mix of Vallejo metal color exhaust manifold and Vallejo metal color chrome.
After that you can go ahead and gloss varnish, do your decal work, paint details (eye lenses, wargear, soft joints etc) and give the models a oil paint pin ash with a dark brown (van Dyke or raw Umber) diluted in odourless artist's sprit.
This might look a bit like Iron warriors but the slight khaki/brownish tint of the exhaust manifold correspond to you picture better and differentiate them a bit from iron warriors, I-d paint details and such so that they really look like DA. Look into ordering superfine checkers decals to put on the shoulder pads like they have on the picture.
The helmets seem to have a greenish tone on the picture so you could do the heads with Scale 75 Peridot Alchemy as midtone instead to give that effect.
Edited by Imren, 13 January 2020 - 02:16 PM.