Using carbon fiber technology, which produces a metal lighter than aluminum, the folks at Windham Weaponry have managed to build a rifle many ounces less heavier than the competition’s. The end product is the Windham Weaponry Carbon Fiber SRC (Sight Ready Carbine), an AR-15-style, direct gas impingement semi-auto chambered in 5.56mm and weighing just 5.85 pounds empty. Writes Jordan, “The same rifle with an aluminum receiver lists at 6.3 pounds. The company has shaved off nearly a half-pound … If that doesn’t sound like a lot, try holding your rifle up to cover in a hallway for a half-hour while your team clears the rest of a house.”