Perhaps the oddest thing about the 223 Remington is how and why it was adopted by the military. They went from 45-caliber to 30- to .22? From 405-grain bullets to 220-grain to 150-grain and then clear down to 62 grain? From 3,000 foot-pounds of energy to 1,300 f-p?
Yes, they did. And in the process we got our most useful, versatile, light recoiling, inexpensive, accurate 22-caliber centerfire cartridge. But sport hunters got it before any military did! Yup. the 223 Remington was introduced as a sporting round before military round. Here’s how it happened…
A few shooters think the 223 should not be used for hunting because it was engineered “as a military cartridge, not a hunting cartridge!” But that’s only half true. The military’s search for a new cartridge that would function to its standards in the new Stoner ArmaLite 15 rifle started with the little 222 Remington, a civilian, sporting 22-caliber that set all kinds of accuracy records after its introduction in 1950. That predates the 308 Winchester, the 243 Winchester, and Elvis as pop star. In 1950 Eisenhower wasn’t even president yet.
As most of us know, the 223 Remington in military circles is known as the 5.56×45 NATO. It’s longer and more powerful than the 222 Remington only because the military looked closely at the 222 and it didn’t quite measure up. It failed because it didn’t retain supersonic velocity (about 1,080 fps at sea level) and penetrate a steel helmet at 500 yards. The Army ordnance department then invited cartridge designers to give it their best shot. I love this part. Rather than design in house using government employees, they allowed, nay invited, ordinary U.S. citizens to create the cartridges! Yankee ingenuity to the rescue.