GunnyGene
Hawkeye
The Army has patented a bullet that may or may not ever show up in the civilian market, and I'm not so sure it will ever make it into the military inventory. The thing seems very limited in practical applications in the field. It's designed to "destabilize" at a predetermined range to avoid unintentional casualties.
Researchers working for the U.S. Army have been award a patent for a revolutionary limited range bullet that self-destructs.
Three employees of the U.S. Army Armament Research, Development and Engineering Center (ARDEC) were awarded the patent for the proof-of-concept projectile, which aims to reduce collateral damage.
The bullet contains both pyrotechnic and reactive material, according to the patent filing, with the pyrotechnic material ignited at launch. “The pyrotechnic material ignites the reactive material,” the patent explains. “If the projectile reaches a maximum desired range prior to impact with a target, the ignited reactive material transforms the projectile into an aerodynamically unstable object.”
The idea here is that once the bullet has reached its range, it simply drops to the ground. McFarlane noted that the distance at which the round “disassembles” can be adjusted based on the type of reactive material used.
http://www.foxnews.com/tech/2016/02/23/army-engineers-patent-limited-range-bullet-that-self-destructs.html?intcmp=hphz03