Mag Research

About

Mag Research is a nonpartisan initiative investigating the use of large capacity magazines in mass shootings. 

Background

Large capacity magazines (LCMs) allow shooters to fire between 10 and 100 rounds without pausing to reload. Often seen on AR-15 style rifles, they are also standard on many handguns. Although LCMs are of no use in hunting and provide minimal benefit in home defense, they are widely used in mass shootings. Nine states and the District of Columbia restrict LCMs, and these laws have been repeatedly upheld in court. 

Data

There is surprisingly little data on the prevalence of LCMs in mass shootings. Previous studies relied on media reports to determine when a large capacity magazine was used, but capacities are rarely reported unless they exceed 30 rounds. Firearms sold standard with 10–30 round magazines are often ignored.

This project compiles magazine capacities of mass shootings from:

• media reports

• agency reports

• gun manufacturer records

• police reports obtained through public records requests. 

All data and sources will be made public.

Status

Research is ongoing. A database will be published on this site when ready.

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