"Investigators say that on Nov. 30, Jared L. Loughner went to a Sportsman’s Warehouse in Tucson, Ariz., and bought a Glock 19, which sells for roughly $500. He is accused of using it during a rampage on Jan. 8 that left 6 people dead and 13 wounded, including Representative Gabrielle Giffords, Democrat of Arizona, who also owns a Glock.... The guns are popular with law enforcement, consumers and, apparently, some young men intent on massacre. Seung-Hui Cho, who killed 32 at Virginia Tech University in 2007, and Steven Kazmierczak, who killed five at Northern Illinois University in 2008, were armed with Glocks."