Tannerite

Tannerite is the brand name of a patented exploding target used for firearms practice, sold in kit form and containing the components of a binary explosive. The explosive comprises a combination of ammonium nitrate and/or ammonium perchlorate (oxidizers), and a fuel - primarily aluminum powder - that is supplied as two separate powders that are mixed by the user. The combination is relatively stable when subjected to forces less severe than a high-velocity bullet impact, such as a hammer blow, being dropped, or impact from a low-velocity bullet or shotgun blast. It is also not flammable – an explosion cannot be created by a burning fuse or electricity. Because it is sold as two separate powders, it can be transported and sold in many places without the legal restrictions that would otherwise apply to explosives. The target system as a whole is the patented, trademarked product called Tannerite, although the term is often used to refer to the explosive mixture itself, and other combination explosives are often generically referred to as Tannerite.

Tannerite is intended to detonate when shot by a high-velocity firearm bullet. Low-velocity shotgun ammunition will not initiate a detonation.

Tannerite detonations occur at a very high velocity, producing a large explosion and cloud. It is marketed as a target designator that is useful for long range target practice: the shooter does not need to walk down-range to see if the target has been hit, as the Tannerite will detonate and serve as a highly-visible indicator.

Tannerite is also used for dramatic effect to provide explosions in weaponry demonstrations or other events. Ordinarily, firing rifle-caliber ammunition will not produce much more than a shattered target or hole (and the sound of the firing) when shot at a target. Using exploding targets can provide cinematic effects such as exploding cars.

For safety reasons, Tannerite recommends using no more than 2 pounds (0.91 kg) of the mixed composition at once, although this guideline is not always followed, and the product can be readily purchased in larger amounts. It is sometimes sold by the pound, and demonstrations of the effects of using up to 100 lb (45 kg) at a time have become popular as internet videos.

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