One of the great things about gun politics in the United States is that if you a) don't really have a dog in the fight and b) are an easily amused nihilist, it's fun to watch both sides repeatedly whip themselves into a fever pitch of self-righteous indignation.

If you're not a ballistics wonk, you may have missed the recent temper-tantrum over the pithily named SS109/M855 Ball, a 5.56 x 45 NATO standard rifle round. That may sound exotic, but it isn't; M855 is a very common type of rifle ammunition, and hundreds of millions of rounds are in the public's hands right now. But there's now talk in the US of banning the round altogether.

Doing so probably wouldn't prevent anyone from using other perfectly legally 5.56mm rounds in his or her perfectly legal rifle. But the round is so common that banning it would be akin to banning computer cloud storage: Workarounds could be utilized, but it would be a huge pain in the ass. And so when the Bureau of Alcohol, Tobacco, Firearms and Explosives (BATFE or ATF) first issued a new rule proposal last month that would have banned the M855, it sparked a huge backlash among gun owners. Which spurred the ATF to back away from the ban earlier this week. Which in turn elicited a huge backlash from gun control advocates.

You spoke, we listened. ATFHQ plans more study on the proposed AP Ammo exemption framework. See more — ATF HQ (@ATFHQ)March 10, 2015

According to those advocates, the ban addresses the fact that some perfidious and irresponsible gun manufacturers have developed handguns that use M855 — which will turn Mayberry into Mogadishu. According to the New York Times editorial board, police lives depend on banning armor-piercing bullets in handguns, and legislation that pushes back against bans by limiting the reach of the ATF is "preposterous."

This excitement all goes back to a 1982 NBC Magazine segment about new Teflon-coated "Cop Killer" bullets — armor-piercing rounds coated with Teflon to reduce the increased wear and tear on a gun barrel associated with firing harder, armor-piercing bullets. Body armor was brand new for police back then, so the idea of a countermove by Criminal Masterminds to defeat cop body armor was red meat for journalists, even if the use of Teflon itself was completely incidental to the ultimate effectiveness of the round.

Four years and a lot of stupid later, the 1986 Law Enforcement Officer Protection Act was passed. It basically set out to ban armor-piercing ammunition use in handguns, leaving us with this sexy little bit of Title 18 U.S. Code § 921(a)(17):

(B) The term "armor piercing ammunition" means—

(i) a projectile or projectile core which may be used in a handgun and which is constructed entirely (excluding the presence of traces of other substances) from one or a combination of tungsten alloys, steel, iron, brass, bronze, beryllium copper, or depleted uranium; or

(ii) a full jacketed projectile larger than .22 caliber designed and intended for use in a handgun and whose jacket has a weight of more than 25 percent of the total weight of the projectile.

The case that the ban is illegal rests on a careful reading of the law. According to part (i), ammunition is considered armor-piercing if it may be used in a handgun and has specific design features. The M855 bullet has a lead core with a steel cap. A steel-core bullet would be considered armor piercing, but since lead — far and away the most common bullet material — isn't on the list of forbidden armor piercing things, the M855 isn't considered armor-piercing under that part of the law.

But in part (ii), the law outlines a second way a bullet can be classed as armor piercing: if the round has a substantial full-metal jacket and is "designed and intended" for use in a handgun. M855's jacket is indeed all metal, but it was certainly not designed or intended for use in a handgun.

So, for the gun-rights folks, the case is clear: The M855 round isn't, according to the letter of the law, armor-piercing ammunition.

As the NRA and other pro-gun groups put it, the proposed ban on M855 is all part of an attempt to put the squeeze on lawful gun owners by banning the ammunition for guns that can't be banned themselves. Their argument goes a little something like this: The Obama administration, finding itself defeated by popular will and unable to browbeat enough people into backing an unconstitutional ban on certain rifles — *cough cough* the AR-15 — developed this as a measure to bypass Congress and illegally impose backdoor gun control on the American public.

'Armor-piercing' is arguably more of a functional description than a binary yes/no thing. A round can pierce a given bit of armor for any one of a number of reasons.

But there's a catch to that narrative. It turns out that, according to any functional definition, the M855 is, in fact, an armor-piercing round — at least for the kinds of relatively light, soft, concealable body armor assumed in this legislation. But so is just about any round fired from a hunting rifle. And getting worked up about that fact is kind of silly.

"Armor-piercing" is arguably more of a functional description than a binary yes/no thing. There's no incantation that magically makes one round armor-piercing and another not. A round can pierce a given bit of armor for any one of a number of reasons: It could be a high-powered round that delivers a lot of energy on impact. Or it could transfer energy to the target in a fashion that minimizes energy loss while maximizing dynamic loads at the point of impact. Or maybe some idiot was using a wadded-up Lynyrd Skynyrd t-shirt for armor, and who cares how the bullet was designed?

An effective armor-piercing round either has a hard metal core (e.g., steel or depleted uranium) that won't splatter on impact, or a jacket that reduces the amount a bullet splatters when it hits the target. These projectiles are better at getting through armor, but are less effective at transferring energy from the round to the target. Regular bullets have a lead core, which is valued for its softness and density — i.e., it's great at transferring lots of energy to the unlucky thing getting shot. Upon hitting a target, a lead bullet splatters and ends up looking like a mushroom. This fatter, wider, duller projectile travels through the target, messing up more things along the way. I'm skipping a number of technical details about yaw, wound cavities, and other dry-but-gory details, but generally speaking, armor-piercing rounds generate less soft-tissue damage.

Alternatively, think of throwing a piece of ice at something. It won't do a ton of damage because it'll tend to shatter on impact. Now think of throwing a rock — it won't shatter, and so it'll do more damage. Now think of launching a Toyota-sized piece of ice at 2,000 mph; it will destroy its target even though it isn't as hard as a rock. Finally, think of underhanding a pebble at something, which won't do much at all.

Point being, even if it makes general sense to say that rocks are more "armor piercing" than ice, it's not a rule. The specific circumstances matter.

The M855, like most rifle rounds, has the power to penetrate soft body armor even if it doesn't have any of those specific "armor-piercing" design features. In fact, the "armor-piercing" design elements people are slap-fighting over are basically just a list of ways that lighter, slower projectiles can punch above their weight when it comes to penetrating armor (or, say, sheet metal).

So why not just test the rounds and avoid parsing all this legalese? Because the NRA absolutely stomped all over the concept of a functional test.

Anyone who knows firearms knows that rifles are, as a general rule of thumb, more powerful and fire bigger rounds at higher speeds than pistols. (Yes, a Desert Eagle makes a bigger bang than a .22 Long, but I'm making a general point here, so hush.) The NRA intuited that if a performance-based test were used to institute a handgun-related ban, some clever soul would compare the banned handgun item to a normal hunting rifle and point out that hunting rifles are more powerful than handguns, and the result would be that rifles would also be banned.

Is the NRA crazy for being so incredibly cautious about creeping firearms regulations? Are gun control advocates crazy for believing that this is all a matter of politicians putting lives at risk, even the lives of police officers, in exchange for campaign donations?

I don't know — though just because you're paranoid doesn't mean they're not after you.

What I do know is that the gun debate in general is crazy. In this current round of screeching, I'm guessing that most of the folks who are normally the rock-ribbed, law-and-order types who have remained pro-police throughout the awfulness in Ferguson are now completely unmoved by this potential threat to police lives. Meanwhile, their opponents in the gun-control movement probably count among their number a huge contingent of people who don't give a good goddamn about cops — unless they're hurling abuse at them — but have now suddenly found police safety an issue of paramount concern.

To paraphrase former NRA president Charlton Heston: "You can have my overheated talking points when you pry them from my cold, dead hand."