The Defense Advanced Projects Research Agency (DARPA) recently conducted successful test-firings of .50-caliber bullets, the agency announced July 10. The ammunition is designed to link with an optical guidance system, which can direct each round to its target. The test employed the Extreme Accuracy Tasked Ordnance (EXACTO) system, which can redirect each round to compensate for weather, target movement, and anything else that could hinder hitting its target.