It’s just 5.56 centimeters long — about 2 inches — and only 5.7 millimeters in diameter at its business end. In its most common American variant, it weighs 12.3 grams. It can reach a muzzle velocity of over 3,000 feet per second, and it is designed to penetrate three-eighths of an inch of steel at … Continue reading Why We Need NATO: The Overlooked Benefits of Interoperability