personally, and this is just my way, paint the handel etc you want to look like wood in a light sand color (let dry) then use burnt umber/burnt sienna oil paint and apply over it. then gently "wisk"/remove the paint (without thinner) with a small brush until you see the sand color showing through. since oils are transluscent, the light color will show through and appear as wood!
here's is an example with my sniper's m-14 rifle
remember this is just my way...someone else's may be different. you can probably get the same general results with acrylics as well. here too is a link from another guy in the forum.
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