308 vs 5.56: Key Rifle Cartridge Differences 308 vs 5.56 is a practical rifle cartridge comparison for AR-platform owners, hunters, target shooters, and new rifle buyers. The .308 Winchester is a full-power rifle cartridge. The 5.56 NATO is a lighter, lower-recoil cartridge commonly used in AR-15 rifles. The short answer is simple. Choose 5.56 NATO […]