The book "Field Artillery Weapons of the Civil War describes gun carriages in chapter 17, pages 213 to 219. The color is described as olive drab applied on the wood parts and black on the metal parts. The authors were James C. Hazlett, Edwin Olmstead and M. Hume Parks and was published in 1983 by Associated University Presses and the University of Delaware.
The metal replica gun carraiges used by the National Park Service are not exact in detail and should not be used as the basis for new build carraiges.

The Artillery Manual by General John Gibbons describes gun carriages in chapter VI page 158.

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