Florida Man must be summering in New England
/Tannerite brand targets explode when shot by a high-velocity bullet. Low-velocity bullets and shotgun ammunition will not initiate a reaction.[1]
The explosive reaction, once initiated, occurs at a very high velocity, producing a large vapor cloud and a loud report. It is marketed as a target designation 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 target will react and serve as a highly visible indicator.
Binary explosives like Tannerite are also used in some business applications, including commercial blasting, product testing, and special effects.[5] Tannerite offers a "boom box" kit which includes colored powder for gender reveal parties.[6][7]
For safety reasons, Tannerite Sports recommends using no more than 1 pound (0.45 kg) of the mixed composition at once, and will sell its largest targets with a size of 2 pounds (0.91 kg) to professionals only.