Okay, let’s talk wound ballistics.
Wait. First, let’s just confess that any culture in which it’s necessary to talk about wound ballistics as they apply to school kids is a fucked up culture. Sadly, that fairly accurately describes the culture in the U.S. right now.
Anyway, a friend who’s a gun enthusiast claimed the AR-15 is no more deadly than any other rifle. Which is a difficult argument to address–not because it’s correct, but because the definition of ‘deadly’ is pretty elastic. Which is why–and the only reason why–we need to talk about wound ballistics.
You hear the term ‘ballistics’ tossed about in police movies and television shows, but what the hell are they really talking about? Ballistics is just the study of the mechanics and behavior of projectiles. Any projectile–rocks thrown by a slingshot, bullets shot by a firearm, missiles launched from a submarine. We’re just going to be talking about bullets here.
First, you need to remember this: a bullet–well, any projectile–displaces air as it travels through it. When you fire a gun, you want a bullet that remains stable as it flies through the air towards the target. In other words, you want a bullet that will go where you aim it. This is what they mean when they talk about ballistics in the movies.
What doesn’t get discussed–and what we need to discuss–is terminal ballistics. That’s the study of how projectiles behave after they’ve arrived at the target. When you apply terminal ballistics to a body of flesh, we’re talking wound ballistics. After a bullet strikes a body, what happens to the bullet? How is the energy of the speeding bullet spent? And what happens to the flesh?
When I was being trained as a medic (a million years ago) my unit was given an object lesson in wound ballistics. The instructors hung a pair of pig carcasses from hooks, one in front of the other, and shot them. First with a standard issue 9mm pistol, then with an old M1 Garand–the .30 caliber rifle that was the standard service weapon in WWII–and finally with an M-16. As you know, the AR-15 is the civilian version of the M-16. We examined the carcasses after each weapon was fired.
Here’s what you need to remember. Just as a bullet displaces air on its way to the target, it also displaces flesh after it enters the target. The 9mm pistol rounds easily penetrated the first carcass, making a tidy little entry wound–a little hole in the body. The bullet remained fairly stable as it hit and passed into the pig’s flesh. Except where they hit bone, the wound track was simple and neat. Even when the bullet struck bone and caromed in a different direction, the wound track remained fairly simple. The 9mm bullets lacked the penetrative power to pass through the first carcass and into the second.
The M1’s larger and heavier .30 caliber rounds made a larger but similar entry wound–a hole in the body. Like the 9mm bullets, the wound track was fairly simple–a hole drilled through the body. Unlike the 9mm bullets, several .30 caliber rounds completely penetrated the first carcass and entered the second. Those bullets became less stable in the second carcass.
Both the 9mm and .30 caliber rounds remained stable as they hit and passed into–and in the case of the .30 caliber, passed through–the carcass. That stability meant the bullets penetrated the body fairly smoothly, displacing a relatively small amount of flesh. Basically, these bullets drilled holes in the carcass. The energy of these bullets was spent passing through the body.
Unlike the other bullets, the M-16’s smaller and lighter .223 rounds remained stable until they hit the carcass, at which point they became wildly unstable. That instability resulted in the bullet lurching and tumbling. Where energy of the stable bullets was expended by passing through–by drilling holes–in the body, the energy of unstable lurching .223 bullets was spent in creating extensive shockwaves in the body. This is called cavitation. It not only displaces a lot more flesh, it means organs, blood vessels, and bone near the bullet’s path are also damaged. The energy of the bullet is expended IN the body instead of passing THROUGH the body. The result is really big, savage, gaping, messy wounds.
What does that mean? For a medic, it means a wound from an AR-15 variant rifle is less amenable to treatment than wounds by a .30 caliber rifle or a 9mm pistol. The AR is more likely to pulp tissue and organs instead of simply passing through them, more likely to shatter bone than simply break it. For a shooter, it means he (yeah, these shooters are almost exclusively male) doesn’t need to be particularly accurate in order to produce a high body count.
In practical terms, this generally means mass shootings involving AR-15 variants will have a higher body count–a bigger butcher’s bill. (I say ‘generally’ because the butcher’s bill depends on more than just the weapon used; it also depends on where the victims are shot. Seung-Hui Cho killed 32 using a pair of relatively small-caliber pistols — but 28 of those victims were shot in the head, and all of them had been shot at least three times.)
My point is that the argument that the AR-15 is no more deadly than any other rifle is a bullshit argument. It’s not about the rifle; it’s about the wound ballistics. A shoulder-launched missile is no more deadly that an AR-15, but the wound ballistics…well, you get my point, right? The story is always the wound ballistics.
