The five gallon steel jerry can is one of the best known items of military equipment ever made. Even in the 2000s, more than sixty years after it was introduced into warfare, it is very common to find auto service trucks or other work vehicles with jerry cans quite like the World War II military ones. The design is still in use because the humble jerry can is very good at fulfilling its purpose.
Huge stockpile of five gallon Jerry Cans of gasoline being prepared for loading on Liberty Ship Martin Van Buren (HR-799), for shipment to Europe, Newport News, VA, Hampton Roads Port of Embarkation, 25 October 1944.
German & British Jerry Cans at the Beginning of WW II
The US 5 gallon gas can originated early in World War II, copied from German "Wehrmachtskanister" or "Benzinkanister" made in the 1930s. The superiority of the German can was recognized by the British and Americans in the North African campaign and immediatley copied, replacing the earlier British "flimsy" can that was subject to leakage and other problems.
Although American production eventually produced a flood of the new standard can, flimsies and captured German cans filled in through the African fighting and into Italy and France. The name "Jerry Can" comes from the slang World War I name for the German soldiers, a tacit salute to the German's superior engineering.
Design of the Jerry Can
The flat, rectangular fuel can has become so well known that an Army jeep looks bare without one on its rear panel next to the spare tire. Officially called "Can, Gasoline, Military; Steel; 5-Gallon" (at least in the 1970s), the Jerry Can has some unique design features that have made it so successful in field use. It holds 5 gallons (or 20 liters), not too heavy for one man to carry or strap to a packboard.
The jerry can has three handles so it is easy to move by hand, one man to the next, in "bucket brigade" fashion or for two men to carry one between them. It is rectangular so can be stacked in large, orderly piles or into trucks, with little wasted space. It has an X-shaped indentation on each side for additional strength. The opening was placed on a slant to the top, and there is a dome behind the handles, so it was not possible to completely fill the can, always allowing for further expansion and maintaining enough air inside so it would float in water. There is an internal air tube to a small hole at the opening so air can replace fuel as it is emptied.
The original closure (British style) had a small lever-action lid over an opening that could be poured from. The American design substituted a wide mouth opening with 4-lug screw lid, closely copied from a 55-gallon drum bung plug. The lugs were placed so a tool could be used for leverage to turn a stuck lid. The American can could be filled or emptied faster, and was easier to clean out, but tended to leak and spill more than the lever-cap British/German approach.
As is often the case, the US Marine Corps was the exception. They procured gas and water cans that had the general size and shape of the Jerry Cans used by the other US services, but utilized a filler cap that was similar to the German/British design: smaller diameter with a lever-action closure. The photo to the left shows Marines and their Jerry Cans arriving at Tarawa Island, November 1943. The filler cap can be clearly seen and distinguished from the flat, 4-lug, screw top of the Army cans.
During World War II and afterward, millions of these containers were produced in the US alone. The Olive-Drab page on Jerry Can Markings has more about who made them and how the cans were marked. The nomenclature for the can became "CAN, GAS, MILITARY, 5 GAL" produced under specification MIL-C-1283. The NSN is 7240-00-222-3088.
Jerry Cans Are Not Just For Gasoline
Even though it is often called a "gas can", the gerry can container is commonly used for everything from diesel fuel to kerosene to jet fuel and so forth. In the military, cans are often stenciled in white, black or yellow over the olive drab base finish with "MOGAS", "AVGAS", "DIESEL" or whatever indicates the contents. The gas can is never interchanged with water (since someone might get poisoned) -- a version of the Jerry Can specially designed for water is used for that.
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