The Defense Advanced Research Projects Agency (DARPA) is testing a new variety of bullet, able to change direction after it is fired. The revolutionary new armament was requested by the Department of Defense (DoD).

The EXtreme ACcuracy Tasked Ordnance (Exacto) will allow snipers to deliver armaments with even greater accuracy than is currently possible. The gunmen are often hampered by dust storms and wind, making it a challenge to hit targets.

"The Exacto 50- caliber round and optical sighting technology expects to greatly extend the day and nighttime range over current state-of-the-art sniper systems. The system combines a maneuverable bullet and a real-time guidance system to track and deliver the projectile to the target, allowing the bullet to change path during flight to compensate for any unexpected factors that may drive it off course," DARPA officials report.

Developers of the Exacto bullet believe the new device will keep American servicemen safe, by reducing exposure. Currently, snipers can reveal their positions if they fire a round that does not strike their intended target. The riflemen usually operate in teams of two people, one gunman and one spotter. Together, they determine how best to aim the weapon, in order to take our their intended victim with a single shot.

The method by which the new bullet changes direction is a tightly-held secret and DARPA officials are refusing to release details on its operation.

Afghanistan is dusty and windy, making it difficult for snipers to successfully hit targets. The Exacto bullet could make it easier for gunmen to hit targets more often with the first shot.

Phase 2 of development involved design of the armament, and test its flight systems, as well as developing means of integrating the bullet into current firearms.

"The EXACTO .50-caliber round and optical sighting technology expects to greatly extend the day and nighttime range over current state-of-the-art sniper systems," DARPA officials said.

The bullet was tested during two rounds of tests, carried out in February and April 2014. Each of the tests were successful, the first time such an armament worked as planned.

Smart bombs and other guided weapons are already being employed on the battleground, and developers believe Exacto is a similar technology. Some observers question whether sniper teams, which already carry significant amounts of equipment, will be able to effectively operate with the additional ammunition. Snipers need to fire a second shot quickly if they miss the first time, and the Exacto system may slow down that ability.

The next steps in testing the bullet will include live fire tests, and improvements to the ammunition.