5.56x45 or 7.62x39?

[WrongHanded]

I'm not saying I'm going to buy an AK (though I'm certainly not buying an AR, so don't even bother), but if I did but an AK I would consider these two cartridges, with no thoughts given to the 5.45x39. I know that the 7.62x39 will probably never be super cheap again. I know the 5.56x45 may be more available in the foreseeable future. This is not about price or availability, it's about performance.

At or inside of 300 yards, is there an appreciable difference in terminal performance? And if so, which one is superior? And please bear in mind that I'm talking about FMJ, not expanding projectiles.

 

[C-grunt]

Out to 300 yards Im going to say 5.56. Inside 100 Id say they are about equal with a possible slight edge to the 7.62x39. However with the lower muzzle velocity and poor BC of 7.62x39 bullets, it loses velocity pretty quickly. It's under 2000 FPS around 150 yards and is running 1575 FPS at 300 yards. Contrast that with a 55 grain M193 and it's still going over 2000 FPS at 300 yards.

Once we add in external ballistics, the 5.56 becomes even better in my opinion.

 

[C-grunt]

In my reply above I used Strelock running a 124 grain at 2400 FPS and M193 55 grain at 3100 FPS.

 

[Beck]

Uh oh... here we go!

My 18-inch barrel Ruger Mini-30 is deadly accurate with plenty of power out to 300 yards. It's a 200+ yard dear rifle. My CZ 527 in 7.62x39 is a 500+ yard target shooter with FMJ. The x39 cartridge is capable. If you load your own to European C.I.P. standards with high BC projectiles like I do, it's more than capable.

Even using good factory ammo with a 123 gr to 125 gr bullet you have roughly the same energy at 500 yards as a 125 gr 357 Magnum bullet at the muzzle from a 4-inch barrel. That's gonna leave a mark.

I went through this process of weighing the pros and cons of 5.56 vs 7.62x39 33 years ago (before I owned a range finder). My conclusion was to buy a Ruger Mini-30 rather than a Mini-14. I have no regrets. this Ruger M30 is still my favorite rifle (carbine).

But of course 5.56 is very capable as well. You might have to toss a coin to decide.

 

[Varminterror]

FMJ’s generally suck for killing anything.

I’d rather have a 5.56, personally.

 

[BreechFace]

My opinion…
7.62x39 8M3
If you know, you know.


But…5.56 is no slouch.

Popcorns *popping*

 

[Beck]

FMJ’s generally suck for killing anything.

I’d rather have a 5.56, personally.

It depends greatly on the design of the projectile. There are so many variations... some good at wounding and some not so good.

 

[valnar]

The 7.62x39 performs poorly for a .30 caliber and the 5.56 performs admirably for a .223 pill, which is why they're pretty close. That said, if you are truly going to shoot close to 300 yards, the 7.62x39 drops another 12" over the 5.56 which is significant.

Everybody has their reasons, but to me the biggest draw to buy a gun with 7.62x39 is for the cheap ammo. Take that factor away, and many other calibers outshine it. And I say this as a 7.62x39 fan with my Vz.58's. (I don't own an AK)

All else being equal, speed trumps size. Both will do their job though. This link explains it all.
https://www.snipercountry.com/5-56-vs-7-62/

 

[Varminterror]

It depends greatly on the design of the projectile. There are so many variations... some good at wounding and some not so good.

Some better than others, but even poor expanding bullets tend to mop the floor with “frangible” ball.

 

[BreechFace]

FMJ’s designed with a void towards the front can do some significant damage as the tumble quickly when hitting a medium.

But I would be remiss in not saying these designs are in existence due to projectile restrictions.

 

[Mosin Bubba]

As a civilian, I don't know why you would limit yourself to FMJ.

For mass blasting, sure, but there's nothing stopping you from keeping a couple mags loaded with the primo stuff.

 

[adcoch1]

If you love the x39 like I do, and practice with it, it is perfect deer medicine to 250 yards, but if the shots are regularly out to 300, the 5.56 is the easy button between the two. Both need good bullets for hunting though. Handholding can drastically improve the x39, and 5.56 doesn't have the extra margin... I wouldn't want to shoot a deer past 300 with either, no matter what loads we're running.

 

[GRIZ22]

I voted 5.56. It's worked for me in real life.

 

[WrongHanded]

As a civilian, I don't know why you would limit yourself to FMJ.

For mass blasting, sure, but there's nothing stopping you from keeping a couple mags loaded with the primo stuff.

No reason at all to limit one's self. However, I like to consider the efficacy of average FMJ, because it's the most likely to be available in a pinch.

 

[CoalCrackerAl]

Good question. I have both 223/556 and 7.62x39. I run FMJ for range play. I also have Speer Spitzer Soft Point 150 grain for 7.62x39. And Hornady 60 grain varmint in .224. So that said. The .224 would fine for ground hogs up to coyotes. Out to and beyond 300 yards. For medium sized game or bad guy. I feel the 7.62x39 would be best out to 300 yards. But you must know your hold over at varied distances in either round.

I run both rounds in bolt action and in AR. And mini 14 in 223/556. I would use my bolt actions for best chance of a hit.

 

[Varminterror]

No reason at all to limit one's self. However, I like to consider the efficacy of average FMJ, because it's the most likely to be available in a pinch.

If we’re playing the “in a pinch” thought experiment, the 5.56 is the answer. 25 years ago, x39 might have been as broadly available, or even moreso, but today, the tide shift has been wholly in favor of 5.56.

 

[WisBorn]

I have owned both cartridges in there favorite platforms an AK and AR. I did not use either for game. I enjoyed shooting the 7.62×39 more than the 5.56×45. On the range I liked how the 7.62 would move my steel plate, the 5.56 didn't move it as much.
In a Mini 14 / Mini 30 platform I would probably go with a 30 because I feel it would be a better defense choice
In a bolt action predator rifle I would like a 5.56 just for a walkabout varmint gun. To defend myself the 7.62.

I will say I have seen poor results with .22 caliber cartridges on deer so my opinion on them is going to be hard to change.

I would prefer a 7.62×51 /308win to reach out to 300 yards. While shooting my 223 varmint rig my group size would open up on the 300 yard range much more than my 300wsm when fighting a light crosswind.

 

[daniel craig]

The one you have is infinitely better than the one you don't.

That is to say, honestly just pick one and roll with it. Practice at the distances you plan on shooting and get good with it.

If you plan on deer hunting with it, at least in my area, commercially available "big game" hunting rounds are hard to find in both calibers, and if I didn't already have an SKS, I'd say neither (for deer hunting). You CAN do it with either round provided you have the right loads but why?

 

[N555]

I found that 7.62x39 fmjs generally did not break up when they hit something and 5.56 fmj bullets normally do fragment, especially 55gr ones.
So if the goal is to shoot through stuff like cars and light cover the 7.62x39 would be better but if varmint blasting the 5.56 would be better.

 

[mcb]

I own two 5.56x45 guns and zero 7.62x39 rifles. In all honest I don't use my 556 guns much except for the occasional 3-gun/carbine match. I love the AR platform but 95% of my use of that platform is with cartridges other than 556.

 

[FL-NC]

In order to get any terminal performance, you need to be able to hit the target. If you can't make this happen, terminal effects are irrelevant. This is easier with the flatter shooting cartridge (5.56/223). Also, the rifles that fire 5.56/223 are generally more inherently accurate than the ones shooting x 39.

 

[valnar]

If you aren't an AR fan and a lukewarm to an AK, you may want to find the rifle first before caliber. If you're starting over from scratch and historical guns or calibers are not important, then I'd definitely sway towards one of the new wonder 6.5 - 6.8mm cartridges. Grendel, SPC, or Creedmoor. They fulfill your requirement more than either 5.56 or 7.62x39. You can add supersonic .300BO to that list.

This is not about price or availability, it's about performance.

I'm not sure what non-AR semi-auto platforms are available that shoot those, but that's a fun google search. Do note that if direct impingement isn't your thing, several piston based AR's are available. I have a PWS MK116 and love it.

 

[CoalCrackerAl]

I do believe the SKS is more accurate VS AK'S. I'll be finishing zeroing in my AR 7.62X39 tomorrow. I'll take my Ruger American bolt action along. And post up target results between them. I'll be shooting Berrys 123 plated. So they are not the best as far as ballistic efficient. But i won't be putting them on paper past a 100 yards.

 

[BreechFace]

An AK with a good iron sight zero is belt-line to top of chest out to 330 yards (~300m) on the first notch "P" or cryllic symbol which is the same elevation as the 300m setting. I would say the vast majority of AK shooters fail to have a good zero on their iron sights, there is a particular way...the Russian way to sight AK's and it's very effective.

I mention the above as the OP was asking 0-300 yard effectiveness.

The 7.62x39 will have more energy out to 300 yards when shooting typical 123gr vs 55gr military ball ammo. The 7.62x39 will have 20% more energy at 100 yards and 23% more energy at the muzzle.

But @FL-NC's point is a good one, when taking typical AK's and AR's more often than not the AR will shoot more accurately.

But if I get to choose my platform for launching said projectile, in a 0-300 yard scenario from a civilian standpoint based on performance alone, I would take the 7.62x39. But to be honest once one gets out 200 yards and on the 5.56 starts looking better.

Now if we are talking logistics, long term patrols, suppressing fire, etc. that changes the dynamics.

Another point worth mentioning is it's easier (to what extent relies on the shooter) to make doubles and triples with an AR in 5.56.

 

[Jim Watson]

I see so much criticism of the 5.56 I wonder what Redworld saw in it to sell the Russians on 5.45 and the Chinese on 5.8.