The M110 155 Projectile is a chemical artillery shell used by the U.S. army. Today, variants of the original shell are used for marking, signaling, and screening purposes. Because they are typically filled with white phosphorus, the shells also have a secondary, incendiary

Incendiary ammunition

-World War I:One of the first uses of incendiary ammunition occurred in World War I. At the time, phosphorus—the primary ingredient in the incendiary charge—ignited upon firing, leaving a trail of blue smoke. They were also known as 'smoke tracer' for this reason. The effective range of...

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Original Design

The original shell, the M110 155mm projectile, was a hollow steel shell that typically contained about 11.7 pounds of sulfur mustard H or HD blister gas

Blister agent

A blister agent, or vesicant, is a chemical compound that causes severe skin, eye and mucosal pain and irritation. They are named for their ability to cause severe chemical burns, resulting in painful water blisters on the bodies of those affected...

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Design variants

There are two design variants of the original M110 155mm shell that are used today; the A1 and A2 variants. Both variants are similar, although differ in some aspects. The A1 is primarily used for signaling and screening, while the A2 is used for screening and marking targets. The A2 weighs about 98 lbs, about 15.6 lbs of which is white phosphorus.