The .223 Remington is a popular, fast-moving, light recoil, and relatively cheap centerfire rifle cartridge. Shooters will use this round in popular rifles such as the AR-15. While similar to the NATO 5.56mm cartridge, the two rounds are not necessarily interchangeable. Owners should be knowledgeable of how their rifles are chambered, what kind of ammunition they are shooting, and what combinations are safe.
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