The Center for Investigative Reporting has put together a lengthy and highly instructive report on how to cover guns and track their history. Their page includes everything from reports from the federal government on which guns are used in crimes the most quickly (time-to-crime) to information on gun manufacturers to federal and state guns laws.

The report can be found here:
http://www.muckraker.org/pg_one_investigation-534-2-0.html [1]

The methodology the Center used for producing its report is available here:
http://www.muckraker.org/content/homepage/GunReportingMethodology.pdf [2]

A page of articles about gun issues can be accessed trough this link: http://www.muckraker.org/pg_inv_by_topic-14-Gun%20Trafficking-0.html [3]

You can also visit their homepage through this link: www.muckraker.org
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