Posted on 06/29/2021 2:20:50 PM PDT by PROCON
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 7.62×51 NATO.
The new M27 Infantry Automatic Rifle chambered in 5.56 during the Marine Corps’ Designated Marksman Course (Official Marine Corps photo by Lance Cpl. Levi Schultz)
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 7.62×51. 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.
7.62×39 (Left) and 5.56×45 (Right) (WikiMedia Commons)
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.
Hard to beat the ol’ 5.56 round. (Official Marine Corps photo by Cpl. Julio McGraw)
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.
At close range, with back-heavy bullets, they can tumble. The hollow cavity of the hollow point bullets(illegal for warfare, I know) contribute to that. They aren’t designed for expansion.
A friend of my brothers was talking about sneaking into range for a shot at some geese in his field. I asked what he was using. He said .22-250 and I just laughed. Sneak into range?
Yes to all of that. Although my ageing eyes forced me to optics a few years ago. Mines an StG58 kit built on a DSA receiver. It’s a tack driver, but I’ll settle for 500 yards. Trigger’s been worked so it has a nice clean break. Definitely a one shot per customer item.
But then there is the issue about the ammo itself. Steel cased East Block ammo is cheap, and runs hot. Wolf isn’t so bad, but it will wear the bore out of your AR variant very quickly (around 5,000 rounds), giving the projectile a keyhole type entrance wound and crappy accuracy.
We always thought that the captured AKs we trained with were just sloppily manufactured with all of the stamped parts - no - it was the worn out chambers from their ammo.
There was a long article posted about the steel cased ammo in here a few months ago - I stopped using it in my AR shortly after that. Keep it on hand for emergency use only.
Short of .338, 7.62x51 is still the best all around cartridge for me. Yeah, heavy. Lots of penetration through cover objects (like both doors of a car) and still quite lethal. I’m done humping SAWs or heavier MGs, and prefer stand off capability using quality glass - too old to clear buildings. Shooting thru them is easier…
Yeah, circumstances have curbed my usual practice. But yes - it’s a comfortable weapon to shoot.
So, the NATO 5.56 cartridge was invented in the 1970s. Gee, it seems very similar to the cartridge used in those Eugene Stoner carbines developed by Armalite. In like 1961 or 1962. And used in Vietnam in the late 60s.
https://www.snipercountry.com/5-56x45-nato-and-ar-15-chronology/
I guess you could say that I don’t find the posted article to be too well-written. Well intended though it may be.
I only use Federal Eagle brass rounds in my Mini-30. The Steel/resin crap ruins the works.
yeah, i reject the premise as well
That the question was even posed is testimony to ignorance on the part of the author.
A 200 grain .30 bullet will have a better trajectory at all speeds than a .22 bullet.
” but for most shooters, the 5.56 round is the better choice for faraway targets”
Effin stupid.
Start with the external ballistics of the two rounds. (I've added a third round that most people would consider a good long distance round for comparison in the bottom row of the chart.)
Cartridge | Bullet | B.C. | muzzle velocity | energy at muzzle | 500 yds velocity | energy at 500 yds | Drop at 500 yds |
---|---|---|---|---|---|---|---|
7.62x39mm | 123 gr | .275 | 2350 fps | 1507 ft.lbs. | 1066 fps | 310 ft.lbs | 123" |
5.56x45mm | 62 gr | .174 | 3077 fps | 1298 ft.lbs. | 1079 fps | 160 ft.lbs. | 88" |
.300 Win Mag | 190 gr | .533 | 2900 fps | 3548 ft.lbs. | 2089 fps | 1841 ft.lbs. | 40" |
What we can see from this is that neither is a very good long range round. Yes, the 5.56mm does shoot a little flatter and is faster, although by 500 yds. that advantage is pretty much used up.
Considering that 1000 ft.lbs. is frequently sighted by hunters as the minimum energy for hunting deer with modern hunting bullets (where the hunters expect expansion), you can see that both of these fall far short of that.
And of course if you are talking military ammo you are talking Full Metal Jacket - less stopping power in soft tissue.
If I were going to be shot at 500 yards with either of these I would pick the 5.56. It's a smaller diameter bullet, it's about 1/2 the weight, but going the same speed.
For long distance efficiency you want a bullet that has a high ballestic coefficient (B.C.) so that it carries speed well over a long distance. Both these rounds have very low B.C.'s (short/light for caliber rounds). They just aren't designed for long range. (And 500 yards isn't THAT long.)
Which is why both military snipers and hunters who expect to have shots on game at longer ranges don't use either of these rounds.
The smallest cartridge you might see a military sniper use is .308 Winchester. The .300 Win Mag is a big step up, and has been used by the US Military since Vietnam as a go-to round.
The long American war in Afghanistan, where really long shots were possible, resulted in even more effective long range rounds including the .338 Lapua, .338 Normal Mag, and .300 Norma Mag. A lot of what the designers of these rounds have done is optimize them for very heavy-for-caliber (and therefore longer, with a higher BC) bullets.
For practical purposes this culminates with the two military .338 calibers, the Lapua and the Norma Mag. Federal makes a 300 grain bullet for these that has a ballistic coefficient of .768, which is very high and will lose speed slowly, thus being a top choice for over 1,000 yard shots.
The .50 BMG was pressed into a the sniper-rifle roll early on in Afghanistan, but it was designed as an anti-material round. The guns that chamber it are by necessity very heavy, and until Barrett built theirs, were always considered "crew served". IE: a few people were needed to hump that thing and run it. The military's Barrett Model M107A1 weighs 29lbs. Their newer MRAD (in .300 and .338) weighs 14.5lbs. Not light, but plausible.
Also, I would hardly describe shooting an AK-47 round as particularly brutal. The .300 Win Mag in a 7.5lb hunting rifle is much worse. But then, it's much more effective at long range, as the chart demonstrates.
Neither are long distance rounds. They were not intended to be.
Xactly.
Hopefully the author isn't the original poster. It's good to ask questions when you don't know things, but not grea to pose as an expert and write articles when you have limited knowledge in the topic.
In a shorter 16” barrel the 5.56 is more accurate. So an AR is going to be more accurate than an AK. But if you do some work on an SKS with a 22” barrel it will be more accurate than either with a 16” barrel because of more pressure build and velocity. I can out shoot either with my SKS and 7.62 hunting rounds. So the rifle absolutely has a lot to do with how accurate a certain round can be. And so can the brand and weight of the bullet.
I consider anything longer than 600 yards, longer distances.
That is way beyond what either of these two should be used for.
I shot 6.5PRC in some PRS competitions and at a few hundred FPS faster than the 6.5 Creedmoor, it was much less susceptible to wind, especially over 400 yards.
So, for a competition round I like 6.5PRC, or if you let me shoot magnum power in competition on your steel, then the 300PRC or 338 Lapua.
If we are talking military applications, 556 up to 400 yards max, 7.62x51 mid-range, and 300WM over 1000 yards.
“I prefer a nice .30-06 for distance.”
That’s what I shoot, both off the shelf and custom.
“For long range stuff I like my Savage .22-250 with 4,000fps rounds. “
A measly 7mm-08 has a better long range trajectory and better energy beyond 200yrds.
Mounting optics is problematic, though.
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