It is interesting to me that a car so near the end of the series is getting a builders photo. One explanation might be that C&O was experimenting to see how a gray car would look, and more importantly, how it would hold up. Gray was, of course, much more common for covered hoppers than black on most roads.
Builder photos were taken when convenient. Sometimes it would be the first car built, often a car somewhere in the middle, and sometimes a car near the end of a number series. Also, you need to be aware that car numbers did not always reflect the ORDER of construction. If one part of an order needed one particular specialty, it might be delayed, so cars could easily be built out of number sequence. But most important, cars (and steam locomotives) that would have final paint that was dark were ROUTINELY photographed in “builder gray,” a water-base paint that was hosed off after the photos were taken. Such builder photos CANNOT mean that any cars were delivered in gray.
