Explosive found in New York blast used for target shooting

Residue from an explosive compound found at the scene of an explosion in a New York City neighborhood is unregulated and routinely used for target practice with exploding targets.

The compound, known by the brand name Tannerite, is sold in sporting goods stores. It is not regulated by the Bureau of Alcohol, Tobacco, Firearms and Explosives because it is sold as a mix of two chemicals that when kept separate are inert.

ATF has previously issued advisories about Tannerite and what it describes as "binary exploding targets." The compound is typically used to mark a shot from a high-velocity rifle round with a small cloud of smoke.

The explosive compounds are generally made up of an oxidizer such as ammonium nitrate and aluminum or another metal-based powder and only become an explosive when combined. The ATF said someone would only need an explosives license to handle the material if it is combined and they are using it commercially.

In a safety notice issued last year, the ATF said users of the compound should not use more of the explosive mixture than recommended by the manufacturer or use multiple packages of the compounds to make a single target.

The ATF also advised that once mixed, the compounds are "high explosives."