Know your ammo

This story was run this morning on CNN.com: Man gives kids 40 mm shell to play with; 2 killed, 5 hurt

BAKERSFIELD, California (AP) -- A military shell given to a group of children by a neighbor exploded while they played with it, killing two children and injuring five others, police and witnesses said.

Police were investigating the cause of Tuesday's explosion, which damaged homes and forced neighbors to wrap bloodied and dazed children in blankets.
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Sendejo told The Bakersfield Californian that he thought the shell was spent and often used it as a "conversation piece." He said the firing pin and bottom shell casing had been removed, along with the gun powder inside.

"I thought it was harmless," he told the newspaper.

It sounds like he got his hands on a 40mm grenade (like that fired from the M203 grenade launcher or the MK19 heavy machine gun). With the firing pin and projective gunpowder removed, that still leaves the grenade intact...which is a problem, as he found. When you recieve war trophies, like this one, make sure you know what it is.