I found instructions out of the US for such a while back, which fact should help in any debates on limiting access to such information in the US. Also note the attempted link to the War On (some) Drugs. -Allen
Pipe bombs: Easy weapons you can whip up at home
_(c) Copyright 1996 Nando.net _
Sacramento Bee
SACRAMENTO, Calif. -- It's no wonder curious teenagers, drug dealers looking to intimidate and thousands of others for unknown reasons are building pipe bombs, experts say: The ingredients are at the hardware store and the instructions on the Internet.
Across the country, latest figures from the U.S. Bureau of Alcohol, Tobacco and Firearms show a 20 percent jump in pipe bomb incidents between 1990 and 1994.
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"We've been incredibly busy," said sheriff's bomb technician Judd Holiday. "As crime in other categories is dropping, this is going up."
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Crude, cheap and surprisingly powerful, pipe bombs are proliferating in part because directions are easy to find on computer networks, experts say. One electronic recipe for a pipe hand grenade ends with the exhortation "Ready to go!"
"It's all over the Internet," said Peter Urrea, resident agent in charge of the Sacramento office of the federal Bureau of Alcohol, Tobacco and Firearms.
Pipe bombs are also an increasingly popular tool of intimidation for makers and dealers of the illegal drug methamphetamine, said Holiday.