Maximum Effective Range 5.56 vs 7.62x39

[GlockFu]

I don't want to start another debate on which round is better as I know there are already tons of them. I keep getting conflicting information on which round has the longer effective range. I'm doing another AR build and want to build it with the intent of greater effective range as I already have short AR 5.56 builds. So will a 5.56 or 7.62x39 give me the farthest effective range?

(I know there's other calibers that will go further more effectively but these are the two calibers I'm choosing from because of costs)

 

[mljdeckard]

I would rather try to hit things at distance with a 5.56.

 

[Robert]

7.62x39 is pretty similar to 30-30 if that helps.

Put a good 20" barrel on an AR as well as a decent float tube, does not have to be railed, and you'd be surprised how far out you can reach. I have made hits on a torso sized steel target at 600y with a rifle set up like that using a 3.5x ACOG. Now that is really pushing the outer limits but it can be done.

 

[NG VI]

No question. Between the two, 5.56. Only one of those calibers is being used in any kind of marksman-oriented role, and it isn't the x39mm.

And I would say, even though you've ruled out others over cost, if you're willing to put up with the miscreant antics of the x39mm in the AR platform, and are interested in range, might as well go with the 6.5 Grendel.

 

[rori]

Just get a loading book and look for yourself. I believe the 30cal wins hands down.

 

[4thPointOfContact]

Well, according to the Field Manual,
M16 has and Maximum Effective Range for Point Targets of 550 meters and 600 meters for Area Targets.
M4 has a Maximum Effective Range for Point Targets of 500 meters and 600 meters for Area Targets. Both are mathematical formulas.

As for the Soviet round, I can't find any published numbers, but I do seem to remember 300 meters being mentioned as being the maximum range where the energy of the cartridge was expected to produce lethal hits. (and That's just a SWAG)

 

[ACP]

A 16" carbine will shoot M855 out to about 90 meters and M193 out to about 140 meters fast enough so the bullet fragments, which is what causes the devastating wounds in a 5.56. They need to be cooking along at 2700 fps or so to do that. Add another 50 meters for a 20-inch barrel.

I'm sorry, I am not familiar with the 7.62x39.

 

[C-grunt]

With the Mk12 being widely fielded there have been many enemy killed at 600+ meters with the 5.56. I know my DMR was accurate enough out to 800ish meters to make effective hits if the shooter was up to the task.

 

[C-grunt]

Plus I believe the standard mil load x39 goes subsonic around 550 yards. It was specifically made for combat at 300 meters or less and it does that range pretty well.

 

[mshootnit]

Here's food for thought: What if you took a quality semi auto and put a 20" match grade barrel with free floating handguard and match trigger. Then you put a Leupold MarkIV tactical scope on the rifle with BDC turrets. Then what if you had it chambered in 7.62X39 and worked really hard at load development to accurately squeeze every ounce of velocity and energy you could get with that 123 gr bullet. How would this compare to 5.56? I think it would fare pretty well in terms of retained energy and terminal performance. And I have not a clue what the max velocity would be but I would be hoping for 2500

 

[rori]

OK my most recent Sierra loading manual gives a 125gr spt bullet 2300 fps and an AR 15 3100 with a 55gr bullet. I'll take the much heavier bullet every time. Also the 30 is legal for deer most everywhere while the 223 isnt.

 

[303tom]

The 5.56 NATO is better at range...............

 

[proven]

effective range for what? two legged targets, 5.56 is your answer.

 

[Z-Michigan]

Several different ways to look at this:

1) Subsonic transition - what distance does the bullet go subsonic, which is the effective limit of accurate fire? Roughly 450-550 yards for x39 and perhaps 600-800 yards for various 5.56 loads.

2) What's the distance where the bullet retains a useful amount of energy or momentum? x39 will be slightly greater than most 5.56 loads, but only slightly.

3) What range can you realistically hit something with factory ammo? Typical x39 ammo has low to middling accuracy. 5.56 ranges from middling to fairly good (Black Hills Mk262 for example). 5.56 also has a much, much flatter trajectory which makes distance estimation less critical. I would say that beyond 100 yards I expect the shooter using a typical 5.56 load to shoot more accurately than someone with a typical x39 load. (Now, if comparing best handloads with expert shooters, the difference might be very small.)

4) What is the overall platform accuracy? This isn't really apples to apples, but if you compare a quality 5.56 AR to a typical x39 AK, the AR will generally be somewhat more accurate. Though not necessarily as much as you would think, especially if comparing a good AK like a Saiga.

If you want greater range in an AR15, I would look at 6.5G and 6.8 SPC in that order. Possibly also 6x45 and 6.5 MPC. The 300BLK would also have some benefit over both 5.56 and x39 on the retained energy side, but not on the trajectory side (and definitely not compared to 6.5 Grendel or 6.8 SPC).

 

[GlockFu]

I'm talking about medium to larger targets so yes, 2 legged targets fall within this range.

I know the 5.56 has more range but out 600-800yrds, is it really going to do any damage? My question is effective range. Does 5.56 still win in effective range?

 

[JohnnyK]

who would really want to shoot that far with either one? I'd go with .50 bmg at that range... I've seen videos comparing 5.56 vs 7.62 x 39 at 100 yards and the 5.56 will only go thru 1 side of a cinder block not the whole thing... 7.62 x 39 will go completly thru the cinder block and have enough left to kill a person on the other side (of course depending on shot placement) 7.62 x 39 has much more power... 5.56 is more accurate each has pros and cons...

 

[mljdeckard]

Yes, it will be effective at that range. Out past a few hundred yards, 5.56 penetrates armor better than 7.62. I never have any question about the effectiveness of the bullet at that range, only my ability to hit with iron sights. And the 7.62x39 runs out of gas a lot faster than a 5.56.

And no, I wouldn't pull out the .50 for ranges like that. If you can't hit it with a .308 within 1000 yards, you won't hit it with a .50 either.

 

[Z-Michigan]

I know the 5.56 has more range but out 600-800yrds, is it really going to do any damage? My question is effective range. Does 5.56 still win in effective range?

There have been a few recorded kills (single aimed shots) at 600-800 yards with an M4 or SPR in Iraq and Afghanistan. They are the exception, and generally have been made by absolute expert shots. Something like Mk262 can still be lethal at those distances, with a mixture of skill and luck. It's not going to be reliable, or even in the same class as a .308. In comparison an aimed single shot of 7.62x39 isn't even likely to hit anything beyond 500 yards due to trajectory, transonic instability and wind drift, though it should be about equally effective if you somehow do manage to get a hit.

If you actually need to shoot at 600+ yards, or even 400+, you really need a .308 or another more powerful distance cartridge (most of the common hunting cartridges like .270, 7mm Mag, .30-06, etc. etc.).

 

[GlockFu]

I don't need to shoot out past 600 or even 400 yards, I am just trying to decide what my build will be with the goal of having the most effective range between these two calibers. I already have close range builds and have another stripped lower so I figured I'd make this one for distance.

 

[Robert]

Get you a nice brisket and hand it on a target stand out at 400 or 600y and have a go at it and see which does better. That would be some real world testing I'd be interested in. At those ranges I believe you'd have a better chance of hitting the target with the 5.56.

Anytime I get a brisket it never makes it past the smoker...

 

[mljdeckard]

(I just bought one to smoke for an upcoming Christmas dinner.

 

[R.W.Dale]

Here's food for thought: What if you took a quality semi auto and put a 20" match grade barrel with free floating handguard and match trigger. Then you put a Leupold MarkIV tactical scope on the rifle with BDC turrets. Then what if you had it chambered in 7.62X39 and worked really hard at load development to accurately squeeze every ounce of velocity and energy you could get with that 123 gr bullet. How would this compare to 5.56? I think it would fare pretty well in terms of retained energy and terminal performance. And I have not a clue what the max velocity would be but I would be hoping for 2500

I built that rifle. Only it was a 26" shilen barreled bolt action. Look at my threads from around four years back for more details.

It shot good out to the longest range I shot it at which was 300m and with higher BC bullets such as the 125g nosler carried a great deal more energy than 223 over that distance.

I guess it really comes down to what its supposed to be effective at.

I've killed deer with a x39 out to 280 yds but I limit myself to 200 w a 223

posted via tapatalk using android.

 

[Matthew Courtney]

If you look at factory loads with higher BC bullets, you will see that past 3-400 yards, the 7.62x39 has lost enough energy that it has less than a .223, and the .223's fly flatter with less wind deflection, but which bullet will expand or tumble to effectively turn the energy into a serious wound? Since we cannot be sure of bullet performance, I opt for the higher probability of hits with the flatter shooting .223.

 

[Ar180shooter]

IMO both rounds are equally effective within 300 yards. Out to 600, the .223/5.56 has the advantage.

**BAC above .08 for this post. Please disregard if nonsensical.

 

[wanderinwalker]

Here's food for thought: What if you took a quality semi auto and put a 20" match grade barrel with free floating handguard and match trigger. Then you put a Leupold MarkIV tactical scope on the rifle with BDC turrets. Then what if you had it chambered in 7.62X39 and worked really hard at load development to accurately squeeze every ounce of velocity and energy you could get with that 123 gr bullet. How would this compare to 5.56? I think it would fare pretty well in terms of retained energy and terminal performance. And I have not a clue what the max velocity would be but I would be hoping for 2500

What you just described is probably 95% of the rifles on the line at a Highpower match, and nobody uses the 7.62x39. (Well, OK, most of them are Service Rifles in .223 anyway, and they're A2s not flattops.) Magazine length 75-77 grain .223 loads work OK out to 600 yards, though longer, sleeker bullets are better. Anybody shooting a .30-caliber past 300 yards is looking at longer and heavier bullets than the 123-125gr bullets the Russian short usually drives. Typical are 168gr .308" match bullets for the .30 shooters, though you can do well with a 155gr Palma bullet, and a 175 is superior on a windy range.

Better than either would be a 6mm or a 6.5mm cartridge, but at that point you're looking at reloading to make it viable (or paying exhorbitant prices on factory ammo! ).

ETA: Just took a quick look and ran the numbers through a ballistics calculator. Drive a 125gr Nosler Ballistic Tip (.366 BC) at 2500 fps and at 300 yards you have 940 ft-lbs of energy and a drop of 21" (7-MOA) from a 100 yd zero. That's not bad considering the low recoil level.