Here you go. Two different browns with the lighter as the base coat, and the dark overlaid. For patterning I used a trout fishing dip net as a stencil.
In the past I've used a honeycomb pattern camo net but I didn't have any handy that day.
Below is the 300 Rum Sendero.
This is the 7mm STW done similarly but with the camo net for the pattern.
What little experience I have at doing camo on rifles has shown me that it's best to go with your lightest color as the base coat, and then overlay the darker colors.