Edited from Wikipedia
Between December 1941 and June 1945, U.S. railroads carried almost 44 million armed services personnel.
There were not enough cars and coaches available to meet the massive need for troop transit duringby World War II. So, in late 1943, the U.S. Office of Defense Transportation contracted with the Pullman Co. to build 2,400 troop sleepers, and with American Car and Foundry (ACF) to build 440 troop kitchen cars.
The new rolling stock was either converted from existing boxcars or built from scratch based on AAR standard 50 foot-6 inch single-sheathed steel boxcar designs, and were constructed entirely out of steel with heavily-reinforced ends. In some instances baggage cars were converted into temporary kitchen cars before ACF could complete its order. The cars were painted the standard Pullman Green and affixed with gold lettering.
Troop kitchens, also known as rolling galleys, joined the consists in order to provide meal service en route.
As the cooking was performed by regular Army cooks, the cars were outfitted with two Army-standard coal ranges. The cars were also equipped with a pair of 200-gallon cold water tanks and a 40-gallon hot water tank; supplies were stocked on open shelves with marine-type railings, a bread locker, a large refrigerator, and a series of built-in cabinets and drawers.
Troops took their meals in their seats or bunks.
The cars served approximately 250 men each, and were typically placed in the middle of the train in order that food could be served from both ends.