I just showed there was no lie. Here, again:
The .223 cartridge was introduced to the civilian market in January 1964, and a few weeks later, in February 1964, the US Air Force adopted the cartridge as the 5.56x45mm for the new M-16 rifles. The .223 was the released to the civilian market as a rifle cartridge for use as a varmint and predator hunting cartridge. This mild recoil cartridge proved popular among other shooting communities. The flat shooting and excellent accuracy of the cartridge were admired by hunters who found it effective on medium size predators, such as coyote, out to 300 yards. Some hunters use it on game as large as deer, but several jurisdictions did not allow the .223 for deer hunting, as the bullet diameter or muzzle energy were not sufficient for a humane kill.