.30 Caliber M1 Ammunition Can in Korea, 20 November 1950.
An early version of the steel M1 .30 cal. ammo can was the T4 "Ammunition Chest, Cal. .30" developed for use in armored vehicles. These cans, usually white/grey or rust-red (like primer) were issued instead of wood boxes because use inside a vehicle required a box with a removable lid. The T4 was not standardized, but the design led to the M1 Ammunition Can for .30 caliber ammunition.
The M1 ammo can typically held a cloth or link belt of .30-06 cartridges. The same box was also used for other cartridges and was stencil marked to indicate the contents, usually in yellow. The box was embossed with concentric rectangles (for strength) and lettering "Cal. .30 M1 / Ammunition Box" on one side with U.S. and the Ordnance flaming bomb on the hinge end. Usually the manufacturer embossed a form of their name above the U.S. (Canco, Reeves, Crown, others.) An embossed cartridge shape indicated the orientation of the contained ammo.
The M1 ammo box had a hinged lid that could be simply flipped up for use or could be removed by sliding it off the hinge. A metal bar handle is attached to the lid by rectangular wire loops so it can fold flat for stacking or lift up for easy carry. On the opposite end from the hinge, a sturdy latch clamped the lid down on its interior edge gasket, making the box almost waterproof. The M1 ammo box was fitted to mount the box to a machine gun.
When loaded with .30 cal. belted ammunition, the M1 ammo can is able to hold a 250 round belt but it can be difficult to fold the belt in such a way that it fits the can and feeds correctly. If you are loading your own cans, you may have to practice this before it will work for you. Linked belts load more easily than cloth belts.
The M1 ammunition box was painted semi-gloss olive drab. Two shades were used, one a little lighter than the other. Both are authentic for this ammo can.
The dimensions of the M1 .30 cal. ammo can are 7.25 inches high, 3.75 inches wide, and 10.75 inches long. It weighs about 22 pounds, loaded.
.30 Caliber M1A1 Ammunition Can
M1A1 .30 caliber ammunition box, Korea, 10 Mar 1952. Note cartridges embossed on the lid.
The .30 Caliber M1A1 Ammunition Can, adopted in June 1945, was developed as an improvement to the M1 ammo can. It is very similar, the same size and intended for use with the same .30 cal. Browning machine guns. It was embossed with M1A1 instead of M1 and had the Ordnance flaming bomb and other markings on the side instead of the end, including the manufacturer (usually United or Artcraft for the M1A1 box). The M1A1 box lid had a cartridge shape embossed on each end to show the orientation of the enclosed cartridges.
Functionally, the M1A1 had a slightly different shaped bottom which allowed up to 275 belted rounds to be stored. The M1A1 box had a rolled seam at the top of the sides, instead of a sharp edge, which improved the seal and preserved the gasket. Underneath the lid latch mechanism is a second latch which is used to mount the can to a Browning Machine Gun tripod.
The M1A1 (as well as the M1) .30 cal. ammo cans continued in use in the 1950s, overlapping the appearance of their successor, the M19 .30 cal. Ammunition Can.
Note: Early M1A1 ammo cans embossed with M1, same as the M1 can. The A1 suffix was added as an overprint. This can cause confusion when trying to properly identify the ammo box.
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