What you will need to paint barrel scorching
Brushes: Small dry brush
Games Workshop colors: Abaddon Black, Rhinox Hide
Paint-to-water ratio: 100:0 for all colors
Techniques: Dry brushing
Dry brushing: After dabbing the bush in the paint, wipe most of the paint off the brush onto dry paper towel. Then apply the paint across the surface of the model, catching the raised areas.
1) First, completely paint the barrel you wish to add scorching to, including any highlighting or washes.
2) Using a small dry brush, dry brush the end half of the barrel with Rhinox Hide.
3) Using a small dry brush, dry brush the end third of the barrel with Abaddon Black.