I’m sure you’ve heard of me. I am one of the most popular cartridges in the world. I’m the caliber of choice for America’s favorite rifle. I’ve been around since the late ’50s and have proven myself an excellent battle, hunting, competition and plinking round. Yep—I’m pretty much the most versatile cartridge in the entire world.
After WWII, the U.S. was seeking a smaller-caliber, magazine-fed, select-fire, semi-automatic rifle to replace the .30 caliber M1 Garand. The military needed a high-velocity rifle that was adequate in close combat. Eugene Stoner’s AR-10 rifle fell short of the requirements. However, in 1956, military officials asked ArmaLite to develop a smaller version of the AR-10. ArmaLite chambered this smaller AR-10 prototype model for .222 Remington.
Initial testing proved the round was not powerful enough. The military needed a cartridge to maintain the speed of sound at 500 yards at sea level. Developers stretched the case of the .222 Remington, so it could hold more powder making the new round faster and more powerful. This round was designated the .223 Remington.
The AR-15 had a short life with ArmaLite. The company sold the rights to the rifle in 1959 to Colt. Colt then entered the rifle into military testing. Ten years later, the AR-15 became the standard issue rifle to the U.S. Army with the designation of M16.
Even though the cartridge had been around since 1957, the Remington Arms Company didn’t introduce the .223 Remington to the civilian market until 1964. The caliber quickly became popular with varminters, benchrest competitors and law enforcement officers.
The .223 Remington has a 0.224” bullet with 40- to 75-grain bullet weight. It has a rimless steel or brass case and can reach velocities up to 3,650 fps. With the right bullet, distance and placement of shot, the .223 Remington is a lethal round for small varmints, predators and medium-sized game.
Part of the .223 Remington’s popularity is its affordability and (previous) availability. The .223 Remington is generally cheap and easy to find. Because of the cartridge’s design, it accommodates a wide variety of bullets for all different types of shooting situations. This aids in the caliber’s versatility when reloading. Since it performs well, and remains a powerful round with less propellant, the .223 Remington does not produce a lot of recoil. That’s why the round makes an excellent caliber for new shooters, young shooters and women.
A Note About .223 Remington v. 5.56 NATO:
5.56 NATO is the military designation for .223 Remington, but it is not the same cartridge. The 5.56 NATO is loaded at a higher pressure (psi) than the .223 Remington. The .223 Remington meets SAAMI (Sporting Arms and Ammunition Institute) specs and has more headspace and a longer throat than 5.56 NATO. To read an extensive explanation of the differences between the .223 Rem and 5.56×45 NATO and which one you can safely shoot in your AR-15, read your owner’s manual and be sure to check out the blog post .223 vs. 5.56: Which Ammunition is Safe for “My” AR-15?