Various shades of khaki. This is like asking which paint is the correct OD Green, (not that again). It varied, there is no one correct color. There were many uniform makers and they all used slightly different die lots that looked slightly different. Also, the colors wore and faded differently. No two sets of web gear were exactly the same colors. The info at US Army Models looks like a good starting point to me.
Corrected link www.usarmymodels.com
Gino P. Quintiliani - Field Artillery - The KING of BATTLE!!!
Check out my Gallery: https://app.photobucket.com/u/HeavyArty
"People sleep peaceably in their beds at night only because rough men stand ready to do violence on their behalf." -- George Orwell