The M548 ammunition container is used primarily as a shipping container for 20MM ammunition and 40mm grenade cartridges. It is often deployed with the Mk19 Grenade Machine Gun, either sitting on the ground or in an ammo can holder on the left side of the weapon.
40mm ammunition in M548 ammo cans standing near a Mk19 grenade machine gun fighting position created by a Soldier from 2nd Platoon, Charlie Co, 1st Bn, 32nd Infantry Regiment, 3rd Brigade Combat Team, 10th Mountain Div, Paruns District Center in Nuristan Province, Afghanistan, 2 May 2007.
The M548 ammunition box is typically used to store and move 20mm or 40mm cartridges, as well as other types of small arms ammunition (eg 7.62mm boxed), and fuses for artillery. When the 40mm cartridges are linked into belts with M16A2 links for the Mk19 grenade machine gun, the M548 ammo can will hold 48 rounds, called the 'USMC Pack,' or 62 rounds bulk packed.
When used as a container for 20mm ammunition, 250 cartridges are bulk packed in each M548 ammo can, weighing 166 lbs. For 20mm machine guns, one hundred cartridges, linked with M14 links, are stored in one M548 weighing 92 lbs.
Filler material, such as foam padding, is used to improve the packing of the various sizes and shapes of ammunition carried in the M548 box.
The M548 ammo box has a handle and a quick-release latch mechanism on each end, very similar to the PA-120 ammunition container although a different size. When both latches are opened, the top comes off, and the box is ready for use to feed a machine gun. A moisture-resistant seal is fitted between the lid and the M548 container.
The M548 ammunition can measures 18 19/32 inches (472.3 mm) x 8 19/64 inches (210.7 mm) x 14 19/32 inches (370.7 mm) in its outside dimensions, weighing 20 pounds (9.1 kg) empty. The M548 box contains a maximum gross weight of 165 pounds (75 kg.) It is defined by MIL-S-23389, drawing number 7258943, SHIPPING AND STORAGE CONTAINER, M548 ASSEMBLY). The M548 ammunition box is covered by NSN 8140-00-739-0233.
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