C-ration

The C-Ration, or Type C ration, was an individual canned, pre-cooked, and prepared wet ration. It was intended to be issued to U.S. military land forces when fresh food (A-ration) or packaged unprepared food (B-ration) prepared in mess halls or field kitchens was not possible or not available, and when a survival ration (K-ration or D-ration) was insufficient. Development began in 1938 with the first rations being field tested in 1940 and wide-scale adoption following soon after. Operational conditions often caused the C-ration to be standardized for field issue regardless of environmental suitability or weight limitations.

The C-Ration was replaced in 1958 with the Meal Combat Individual (MCI). Although officially a new ration, the MCI was derived from and very similar to the original C-Ration, and in fact continued to be called "C-Rations" by American troops throughout its production life as a combat ration (1958–1980). Although the replacement for the MCI, the MRE, was formally adopted as the Department of Defense combat ration in 1975, the first large-scale production test did not occur until in 1978 with the first MRE I rations packed and delivered in 1981. While the MRE officially replaced the MCI in 1981, previously packed MCI rations continued to be issued until depleted.

The first U.S attempt to make an individual ration for issue to soldiers in the field was the "iron ration", introduced in 1907. It contained three 3-ounce cakes (made from a concoction of beef bouillon powder and parched and cooked wheat), three 1-ounce bars of sweetened chocolate and packets of salt and pepper. The ration was issued in a sealed tin packet that weighed one pound, to be carried in infantrymans' top tunic pockets, and was designed for emergency use when the troops were unable to be supplied with food. It was later discontinued by the adoption of the "Reserve Ration", but findings from the development and use of the Iron Ration went into the development of the emergency D-ration.

The Reserve Ration was issued during the later part of World War I to feed troops who were away from a garrison or field kitchen. It originally consisted of 12 ounces (340 g) of bacon or one pound of meat (usually canned corned beef), two 8-ounce (230 g) cans of hard bread or hardtack biscuits, a packet of 1.16 ounces (33 g) of pre-ground coffee, a packet of 2.4 ounces (68 g) of granulated sugar, and a packet of 0.16 ounces (4.5 g) of salt. There was also a separate "tobacco ration" of 0.4 ounces (11 g) of tobacco and 10 cigarette rolling papers, later replaced by brand-name machine-rolled cigarettes.

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