The capability of a soldier to carry his own supply of water is one of the most basic items a uniform design most figure out. In World War I, the Quartermasters came up with an effective yet basic design that was utilized with slight modification over decades of service. The M-1910 1 quart canteen utilizes an metal canteen, which rests in a metal cup with a folding handle, and together are house in a canvas cover that can be attached to a belt. The design is fairly compact and easy for a soldier to reach. By the time America was gearing up for possible involvement in the second world war, there was little modification to the pre-existing design. The canteen cover was made sturdier and the cup and canteen easier to make with materials not previously available.
You WILL need to drink water, therefore you WILL need a canteen! We can not stress that enough. That being said, canteens are easy to find and relatively inexpensive. You can go with the World War One, M-1910 style, or anything later. Whatever you can find, really. Once again, darker green canvas usually signifies later war, bon't be deterred from this if that's what you have. We'd rather you'd be able to drink water in the field (and not mooch of our canteens) than not at all. You shouldn't have trouble finding a correct looking canteen, though.
Three things need to be looked at when buying for the canteen system: The Canteen, The Cup, and The Carrier. Really, any US design that you find is good for us. You can mix an M-1910 canteen with a cover dated 41. Troops got whatever the Army gave them and if left over WW1 supply was what was in stock, then that's what the soldier got. To know the difference, here's a break down:
Canteens
WW1 and Pre-War canteens are easily noted by their metal cap (usually ridged to aid in grip) when it is sitting in its cover. Once it is removed, you will see that the body of the canteen is actually two halves, with the split running along the sides of the canteen up to the neck, and soldered together. WW1 canteens often come with some corrosion due to their age water drunk out of them may have a metallic taste to it. It is possible to clean out the inside (which we recommend) by a variety of means which we will not go in to detail here. Should you come across a decently priced M-1910 canteen, we recommend you get it and we can show you how to clean it out.
The canteen issued in the 40s and during the war was also of two piece construction. However, the seam here is at the center of the body, halfway up the canteen and running the circumference of it. When placed in the cup, the lip will seat nicely at this seam. The cap has also changed and is now black bakelite or plastic. These are relatively easy to find.
Some experimental ones were a ceramic enameled canteen (usually black or olive drab) and a synthetic ethocel canteen (often orange in color). It's not too common you'll find these as they were issued in limited numbers, but it's good to know what they are.
Cups
Canteen cups didn't change much between the two wars. They still have a handle that folds out from the body and locks in to place by a sliding tab. The way to differentiate the two is that older models have a lip that is rolled over whereas the new version was more "stamped" and flared out from the cup. The flared lip style didn't transfer as much heat to the soldier's lips as did the rolled type. Again, either cup will do.
Covers
The canteen, with the cup, sit in a canvas cover. These covers have two flaps with Lift The Dot fasteners. Marine covers have flaps that actually criss-cross and won't work for an accurate Army impression. On the back of the canteen has the same kind of hooks that allow it to be suspended from a belt. There are several variations of this suspension system. The earlier version has the tab sewn directly on to the canvas with no reinforcement. These tend to tear after days and days of a soldier running around and it getting snagged on things. The weak points were the actual canvas tearing, not the webbing material, making it difficult to repair without replacing the canvas altogether.
Thus, a solution came about by sewing a piece of webbing across the suspension anchor point to help distribute the wear over the canvas. The result was pretty effective. You may also come across a canteen cover with an extender strap. This is a removable strap designed for mounted infantry. The strap lowers the canteen off the hips, making it an ideal for paratroopers not interested in landing on their canteen with their backs, and the removeability is great for soldiers who need to jump in and out of a drivers seat.
Colors can vary, per the usual with WW2 equipment. Most desirable is the olive drab color. Older stuff may appear khaki because of fading due to age. Later war is going to be darker green, of course. Stuff in between may have a two-tone look, OD canvas with a darker green trip or thread. All are okay.
Featured in the picture above, from left to right, is a canteen cover, 1943 dated with a reinforcing strap sewn over the suspension anchor; a rolled lip, M-1910 cup; a flared lip cup; a mid-war canteen with bakelite cap; and an M-1910 canteen with all aluminum construction. Note the different locations of seams on the two canteens.
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