Are mass shootings committed with a shotgun more lethal than those committed with a semiautomatic rifle?

Friday, June 10, 2022
By Lisa Freedland

The most lethal mass shootings have all been committed with semiautomatic weapons —either rifles or handguns.

Mother Jones keeps a database of mass shootings dating back to 1982. Of these, six of the 10 most lethal incidents were committed with a semiautomatic rifle as the primary weapon. Within the top 30, only one incident involving a shotgun as the primary weapon is present, at number 29.

The database also suggests that semiautomatic rifles are used more frequently than shotguns in mass shootings. Only six of 129 documented incidents were committed with a shotgun as the primary weapon.

A 12-gauge shotgun is more powerful than an AR-15 at close range and expels more fire. However, shotgun pellets and slugs more rapidly lose power with distance and are less accurate vis-à-vis AR-15s. The long-range lethality and precision of semiautomatic rifles contribute to their frequent use by mass shooters.

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