According to a report in the Telegraph newspaper there has been a new record set for the longest kill shot in Afghanistan.

GPS aids supposedly "measured the distance the bullet traveled at 2815 meters", beating the previous record of 2475 meters for a confirmed kill.

The shot was taken by a commando sniper team in Helmand province, Afghanistan.

“Through binoculars at a distance invisible to the naked eye they spotted a group of Taliban. The soldiers having means of identifying targets went through a process of obtaining verification and permission to engage. 

Two marksmen using Barrett M82A1 50 caliber rifles simultaneously fired. The bullets were six seconds in the air. One killed the Taliban commander. It is not known for certain which sniper fired the fatal shot. While there have been no triumphant press releases, in the tight global Special Forces sniper community the shot is much discussed, because it seems certain to be a world record” 

The M82A1 50 caliber is a recoil-operated, semi-automatic anti-materiel rifle developed by the American Barrett Firearms Manufacturing company. A heavy SASR (Special Application Scoped Rifle), is in use by many units and armies around the world. 
(Examiner)