The above link is a journal entry I wrote comparing different cartridges using the Taylor Knockout Factor. It's a formula developed by a famous hunter that determines effectiveness based on bullet weight, speed, and diameter.
The .223 cartridge has gained infamy lately in the media. It's considered a large caliber high powered cartridge. On the list of cartridges compiled in the entry the .223 is actually pretty weak. Only .22lr and other rimfire cartridges.
The big hype about .223 is that it's a light weight cartridge you can carry a lot of and that it's a high velocity cartridge. The light weight factor is pretty spot on, but it's a trade off. The small diameter bullet is such a light weight it's not as effective as the other cartridges. Most rifle cartridges are about 2800-3000 feet per second while .223 is closer to 3300. That's about a 10-15% increase in speed, but at the sacrifice of about 60% bullet weight and about 25% diameter.
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