I wanted to get the cool little barricades from Kill Team: Octarius finished up quickly, but in a similar way to the official Games Workshop art. This is what I came up with.

1. Prime your barricades. I would recommend using a light grey, if you have one available.
2. Basecoat with a light-ish grey. I used Cold Grey, which is close to Dawnstone.
3. Apply a heavy drybrush of a lighter grey. I used Stone Wall Grey, but Administratum Grey is the Games Workshop equivalent.
4. Now give the barricades a quick coat of gloss varnish. I used Vallejo gloss varnish through an airbrush, but you could use a spray can like Munitorum Varnish.
5. Pin wash the recesses and around nuts and bolts with a brown oil paint. I used Burnt Sienna from the Winton series.
6. I did another pin wash, now with Burnt Umber. With this step I only popped oil paints in horizontal recesses and shadow areas.
7. Pop some Agrax Earthshade into the bullet holes, just to make sure they are extra dark.
8. Now I would advise sealing in the oil paints with another coat of varnish.
9. Drybrush all the edges and rivets again, lightly this time, using Ulthuan Grey.
10. Basecoat all of the mechanical parts on the back with a 1:1 mix of Leadbelcher and Abaddon Black.
11. Edge highlight the metallic components with pure Leadbelcher.