For most shooters the difference between .223 Remington and 5.56×45 NATO is minor, but it matters because 5.56 is typically loaded to higher pressures and uses a slightly different chamber leade.
The United States has tested a specialized 5.56×45 mm anti-drone ammunition designed to intercept FPVs and small quadcopters at close range. The round allows a conventional assault rifle to serve as a ...