5.56 NATO vs .223 Remington: Which Should You Choose?
Woody's answers are based on published federal and state law. Not legal advice. Consult a licensed attorney for your specific situation.
Choose 5.56 NATO for versatility and military surplus availability. Choose .223 Remington for precision shooting and consistent commercial loads.
How This Affects Your Shooting
The choice between 5.56 NATO and .223 Remington affects your barrel selection, feeding reliability, and ammo compatibility. While often considered interchangeable, these cartridges have different pressure specifications and chamber dimensions that impact performance. Your decision influences everything from accuracy potential to long-term barrel life.
The Detail
The fundamental difference lies in chamber pressure and dimensions. 5.56 NATO operates at higher pressures and uses a longer throat, while .223 Remington chambers are cut tighter with a shorter freebore. This means 5.56 NATO ammunition generates more pressure than .223 Remington loads, affecting both performance and safety considerations.
Chamber compatibility creates a one-way street. You can safely fire .223 Remington ammunition in a 5.56 NATO chamber, but firing 5.56 NATO rounds in a .223 Remington chamber can create excessive pressure. Many manufacturers now cut .223 Wylde chambers as a compromise, offering better accuracy than 5.56 NATO chambers while maintaining safe compatibility with both cartridges.
Accuracy characteristics differ noticeably between the two. The tighter .223 Remington chamber typically produces better precision with match-grade ammunition, making it preferred for competitive shooting and precision applications. The 5.56 NATO chamber trades some accuracy potential for reliability with a wider range of ammunition types and conditions.
Ammunition availability and cost present practical considerations. Military surplus 5.56 NATO offers budget-friendly bulk shooting options, while .223 Remington dominates the precision and hunting ammunition market. Commercial .223 Remington loads generally show more consistent quality control and better accuracy potential than surplus military ammunition.
Build Impact
For a general-purpose rifle, choose 5.56 NATO chambering to maximize ammunition compatibility and take advantage of surplus availability. If you're building a dedicated precision rifle, .223 Remington or .223 Wylde chambers will better serve your accuracy goals.