Some of these rumors were created by the military to make the troops more comfortable with using a gun that was far less powerful than the AK-47's that our troops were facing, and much weaker than the hunting rifles they had used at home. But sometimes weaker is better. Wounded soldiers cost more resources than dead ones, and lighter guns/rounds are easier to carry and shoot: and that's why the military chose it. But the facts are that.223 isn't even the most powerful varmint round, and is one of the weakest of the rifle rounds. It is so weak that it can't be used to hunt deer or larger game in many states. Anyone trying to sell this AR-15 bullets are more deadly than other rifle bullets, is either a fool or a propagandist. And if they're a media organization with a single fact-checker, you know which one.
Creation of an assault rifle
Assault Rifles were created by Germany in WWII. The idea was ordinary rifle rounds were way overpowered for the "average" firefight, which was less than 400 meters and in urban settings, most soldiers weren't good shooters at beyond that range anyways. So lighter guns and rounds would make it easier for most troops to maneuver, fire and carry more ammo. And that's what an assault rifle was -- a weaker and lighter version of a military or hunting rifle, to be used for shorter ranged combat.
Most military's adapt slowly to change at it took until the late 1950's that the U.S. started rethinking their .30 caliber (large round), and started looking for a better replacement for the M1/M14 -- and started taking bids for what would become the M16. A small arms company called Armalite had made an AR-10 for earlier military use: this was a full power 30 caliber (7.62 or .308) based weapon, but only got contracts from Sudan and later Portugal. But they also had decided to make a lighter variant that was the AR-15, in the much smaller varmit sized round called the .223 remington, and that enabled them to make a lighter gun.
A bullets momentum (potential damage) is based on the diameter (caliber) and weight of the bullet, the amount of powder that pushes the bullet, and the length of the barrel (since the powder has more time in barrel to accelerate the bullet). Physics 101 : momentum = mass * velocity. A slow heavy bullet can hit with the same force as a faster and lighter bullet... just like a coin and a nail might weight the same and be traveling the same speed (thus have the same energy), but they have different ballistics and different impact characteristics. Generally, the faster bullet drops less over the same distance so is easier to control, and the thinner a bullet it, the deeper it penetrates -- but if you go through an object, you gave up potential impact energy. You can read more at Bullet Basics.
Remington modified their .222 and created the .223 -- which was slightly faster than the .30 caliber rounds they had been using, but it was slower and less lethal than other varmint rounds at the time, and nowhere near as powerful as other hunting weapons. This round is so weak, that it's not even legal to hunt Deer or larger animals with it, in many states.
When someone says something retarded like the .223 is uniquely powerful, I try to find more polite euphemists for ignorant fool or a liar, but no matter how many linguistic gymnastics I try, they always seem insulted by the truth. But it is the truth, they are wrong -- the only question is how resistant to learning are they.
You measure a bullets power by energy delivered in ft lbs... velocity (depth of hole) and caliber (size of hole) can matter too on lethality, but basically, it's how much energy the round has to impart that matters the most.
For a baseline:
- .223 is about 1,300 ft lbs (3,000 fps) -- and is designed for about 400 yards.
There's a little slop in that you can use a lighter/faster bullet, or heavier slower one, and some variations in energy/speed, but this is an average (all are shooting 40-65 grain bullets).
Large Caliber Pistol Rounds:
- .44 Magnum ≈1,500 ft lbs (1,500 fps)
- .50 Action Express ≈1,600 ft lbs (1,500 fps)
- .600 Nitro Express ≈8,400 ft lbs (2.000 fps)
In .22 calibers we have the following:
- .220 Swift ≈1,800 ft lbs (4,000 fps)
- .22-250 ≈1,750 ft lbs (4,000 fps)
- .22 Eargesplitten Loudenboomer ≈2,349 ft lbs (4,500 fps), you can see it compared to the .30-06 (which is a lot bigger than any .223) pictured to the right. Now the EL was a novelty round created to break the 5,000 fps barrier (but didn't). Yet the point is that the .223 is not that fast/powerful a round, even in the small caliber rifle bullet range.
So they're wrong on the .22 caliber rifle rounds, the .223 wasn't close to the top bullet in that caliber. But remember, the .223 was meant as a light varmint round replacement for the .308 and .30-06 medium hunting rounds that were used in WWII.
Normal Hunting Rounds:
Now the .308 and .30-06 are both mid-game hunting rifles that got converted to military use.
NOTE: I had one guy implying that you can get certain light bullet flavors of the .223 that go faster, or was arguing small +/- differences of the ballistics: which is true. I'm using normal ranges, and you can do things with rare/custom loads: but that's not the normal bullets. And if you're using special loads of .223 to get what you want (that no mass shooter is using), then you can buy special things like putting a .223 in a sabot in a .30-06 bullet (the sabot is a wrapper that comes off in flight), and that still makes the .30-06 w/.223 bullet, a MUCH faster bullet. But it's silly, we're talking normal loads, and none of it changes the point that bigger bullets can do more damage.
Big Game Rounds:
- In 1870 we had the famous Sharps Buffalo Rifle ≈ 2,900 ft lbs (2,000 fps)
- In 1912 the .375 H&H Magnum became popular big game round with ≈4,500 ft lbs (3,000 fps)
- A popular modern sniper round is the .338 Lapua Magnum ≈ 5,000 ft lbs (3,000 fps)
- And the .700 Nitro Express is an elephant gun with ≈8,900 ft lbs (2,000 fps)
- The military long range sniper rifle is .50 Caliber BMG ≈14,000 ft lbs (3,000 fps)
The M16 was lighter, had a recoil reduction spring/weight, and was easier to shoot (and had a handle). But while the .223 is a better round that the .308 (7.62) in 80% of cases, and marksmanship tests between the two bore that out, it's hard to sell that idea to troops. "Yes, it's a lighter powered gun than the AK-47 or old M14, but you can hit more people with it, and carry more ammo" isn't a tradeoff most grunts want to hear. Plus it was plastic, and toys are made of plastic. So they military had an uphill battle.
Enter, the rumor mill. They started selling bullshit -- "it's a smaller round, but it spins so fast, that when it hits, the bullet turns sideways and hits like a much bigger round", and "it spins so fast, it'll bounce around on their insides".... and the ever famous, "I've heard of guys getting shot in the foot, and the bullet comes out the top of their head". Total crap like that, that will impress neophytes and high school drop outs, as well a few ignorant folks in the media. And it worked, the stories spread, and soon everyone knew someone that knew someone who had these fabulous stories about the new M16 (.223). But the truth is, if you were a really good shot, they gave you the .30-06 sniper rifle, not the M16, because they wanted you to have the real firepower.
So if you hear someone repeating the stories, you know it's just stories. Physics doesn't work like that, bullets can't turn 90° when they hit water, and a .223 doesn't have enough energy to travel stem to stern though a human body (especially if it nicks a bone). And you don't want bullets to be that overpowered because if they do, they're going through people, instead of stopping inside them. And stopping inside is when they do more damage (deliver more energy).
Guns and ammo are about tradeoffs. The bigger the bullet (and powder) the heavier it to carry ammo, and the harder it is to shoot well. Most firefights were a couple hundred yards away -- so the old style hunting rifles (designed for 400 yrds+) gave way to lighter Assault Rifles that are good to about 300 yrds. Also killing people in war, may not be as important as maiming them, so lighter rounds can do that better. Thus, we went to light varmint rounds for our military.
Now all bullets are designed to kill, but only clueless people say things like the .223 was uniquely designed to kill humans. It was a balance between hotter varmint rounds that could do more damage to humans (but required more maintenance), and one that was lighter and would be easier for most people to shoot. The military doesn't care, because maiming a soldier takes more people off the battlefield (caring for them) and causes more damage to morale and fighting forces than killing them does. So if there was an intent by going to lighter rounds, it wasn't about more kills, but more hits. If we wanted to kill more people, we can make exploding rounds, or thorium/mercury/poisoned rounds that will kill anyone they hit. If anything, the round was designed more to maim than to kill. So any time you hear an expert selling you a line of bullshit, you'll now know better.
For a few hundred years we've been playing with ballistics to try to get the right balances of ease of shooting, and power. Most civilians that are into AR platfiorm guns aren't even into the .223/5.56 -- the 6.5 Creedmore is becoming more popular amongst the AR-10 crowd as a longer reach bullet, and the .300 blackout is the hot new thing amongst the shorter range AR-15 crowd. They wouldn't be doing that if the .223 was the ultimate killing cartridge.
In the end, if you start getting a dose of hype from the media or a media personality, about how uniquely deadly the AR-15 platform is, you know they're an idiot or a propagandist. And if the moderator doesn't immediately call them on it, you know that station either doesn't have a competent fact-checker on their staff, or they're trying to sell the gullible on the their political agenda.