Unless you're an avid shooter, there tends to be only a handful of ammunition types a person can list off the top of their heads, and even fewer if we're talking specifically about rifles. Although there's a long list of projectiles to be fired from long guns, the ones that tend to come to mind for most of us are almost always the same: 5.56 and 7.62, or to be more specific, 5.56×45 vs. 7.62×39.
National militaries all around the world rely on these two forms of ammunition thanks to their range, accuracy, reliability, and lethality, prompting many on the internet to get into long, heated debates about which is the superior round. Of course, as is the case with most things, the truth about which is the "better" round is really based on a number of complicated variables -- not the least of which being which weapon system is doing the firing and under what circumstances is the weapon being fired.
This line of thinking is likely why the United States military employs different weapon systems that fire a number of different kinds of rounds. Of course, when most people think of Uncle Sam's riflemen, they tend to think of the 5.56mm round that has become ubiquitous with the M4 series of rifles that are standard issue throughout the U.S. military. But, a number of sniper platforms, for instance, are actually chambered in 7.62x51 NATO.
So if both the 5.56×45 vs. 7.62×39 rounds are commonly employed by national militaries… determining which is the superior long-range round for the average shooter can be a difficult undertaking, and almost certainly will involve a degree of bias (in other words, in some conditions, it may simply come down to preference).
For the sake of brevity, let's break the comparison down into three categories: power, accuracy, and recoil. Power, for the sake of debate, will address the round's kinetic energy transfer on target, or how much force is exerted into the body of the bad guy it hits. Accuracy will be a measure of the round's effective range, and recoil will address how easy it is to settle the weapon back down again once it's fired.
The NATO 5.56 round was actually invented in the 1970s to address concerns about the previous NATO standard 7.62x51. In an effort to make a more capable battle-round, the 5.56 was developed using a .223 as the basis, resulting in a smaller round that could withstand higher pressures than the old 7.62 NATO rounds nations were using. The new 5.56 may have carried a smaller projectile, but its increased pressure gave it a flatter trajectory than its predecessors, making it easier to aim at greater distances. It was also much lighter, allowing troops to carry more rounds than ever before.
The smaller rounds also dramatically reduced felt recoil, making it easier to maintain or to quickly regain "sight picture" (or get your target back into your sights) than would have been possible with larger caliber rounds.
The 7.62x39mm round is quite possibly the most used cartridge on the planet, in part because the Soviet AK-47 is so common. These rounds are shorter and fatter than the NATO 5.56, firing off larger projectiles with a devastating degree of kinetic transfer. It's because of this stopping power that many see the 7.62 as the round of choice when engaging an opponent in body armor. The 7.62x39mm truly was developed as a general-purpose round, limiting its prowess in a sniper fight, however. The larger 7.62 rounds employed in AK-47s come with far more recoil than you'll find with a 5.56, making it tougher to land a second and third shot with as much accuracy, depending on your platform.
So, returning to the metrics of power, accuracy, and recoil, the 7.62 round wins the first category, but the 5.56 takes the second two, making it the apparent winner. However, there are certainly some variables that could make the 7.62 a better option for some shooters. The platform you use and your familiarity with it will always matter when it comes to accuracy within a weapon's operable range.
When firing an AR chambered in 5.56, and an AK chambered in 7.62, it's hard not to appreciate the different ideologies that informed their designs. While an AR often feels like a precision weapon, chirping through rounds with very little recoil, the AK feels brutal… like you're throwing hammers at your enemies and don't care if any wood, concrete, or even body armor gets in the way. There are good reasons to run each, but for most shooters, the 5.56 round is the better choice for faraway targets.
Feature image: U.S. Army