It was a Glock 17.
guardian.co.uk/uk_news/story/0,3604,1535984,00.html
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[...] an initial two-week training course in the use of the Glock 17, which was the weapon that killed Jean Charles de Menezes [...]
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The Glock 17 is a 9mm and is standard issue at most police departments in the U.S. It uses double stack magazines and the police-only magazine hold 17 or 19 rounds. Extra-long magazines hold 31 rounds, but these are plainclothes police officers who might look funny with giant magazines sticking out of their concealed guns.
The Glock 18 is a factory full-auto Glock 17.
remtek.com/arms/glock/model/9/18/
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The G18C looks like a standard Glock 17 9x19mm handgun. Whatever carry method is good for a handgun is the same for the G18. It is a very non-threatening piece of equipment. No bad guy, spectator or news reporter would have a clue until the gun is fired.
The G18 is controllable and will not spray bullets indiscriminately all over the area, despite the 50 to 70 years of bad press that has accrued to the concept of shooting a hand-held machine pistol. Common wisdom is that you can not hit anything with the gun without a shoulder stock, and even with the stock it is still an iffy proposition. Common wisdom has not shot a Glock 18!
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