But like many terms in the firearm lexicon, a high-capacity ammunition magazine means different things in different places.
In California, considered by many to have some of the strongest gun laws in the country, a large-capacity magazine is one that holds more than 10 rounds. In Illinois there is no state law regarding magazines. Yet, there are laws regarding magazines in Chicago where the threshold is more than 12 rounds. But about 40 miles away in Aurora, Ill., this type of magazine is called a large-capacity ammunition feeding device and means anything more than 15 rounds.
In 44 states, including Arizona, Colorado, Connecticut, Texas and Virginia where these magazines have been used in deadly mass shootings, there are no laws against using them, according to a 2012 analysis by the Law Center to Prevent Gun Violence. If a federal law banned magazines that hold more than 10 rounds, it would become the minimum standard.
The definition of "assault weapon" also varies. There is no federal definition of an assault weapon, and the meaning of the term is inconsistent even within the gun industry. California defines an assault weapon as a "firearm (that) has such a high rate of fire and capacity for fire-power that its function as a legitimate sports or recreational firearm is substantially outweighed by the danger that it can be used to kill and injure human beings." The law specifically lists 60 rifles, 14 pistols and five shotguns. Neighboring states Nevada and Arizona have no assault weapon restrictions.
Federal law does not prohibit the ownership of any weapon, said Ginger Colbrun, an ATF spokeswoman in Washington. In order to buy or own certain firearms, including automatic weapons, machine guns and bazookas, people do have to apply for permission from the federal government. But as long as the application for a restricted firearm is approved, and there is no state law barring ownership of that type of gun, it's legal.
"There is such a variation in the number of laws that regulate the distribution of guns that there is no adequate minimum standard," said Richard Aborn, president of the New York-based Citizens Crime Commission. "The federal government has an obligation to establish at least minimum standards that have to be complied with before a gun can be sold anywhere in America."
Associated Press writers Jack Gillum and Alicia A. Caldwell contributed to this report.
Follow Eileen Sullivan on Twitter at http://www.twitter.com/esullivanap .
Copyright 2013 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.