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 lethal range of typical 7.62x39mm ammo?
MichigamaGunslinger  [Team Member]
8/19/2010 7:21:36 PM EST
To start off with, those of you who read the AR ammo forum may have noticed a very similar post by me regarding 5.56mm ammo. I'm not trying to start a pissing match, just looking for useful facts/insight.

So anyway, what is the lethal range of typical 7.62x39mm ammo? The maximum range at which a center mass shot would be lethal with one round (on human/medium size game targets). The barrel in this equation would be 16" long. I was hoping out to something like 350m, but my instincts tell me something more along the lines of 250m.

So what does the hive think about this?
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KILLERB6  [Team Member]
8/19/2010 9:01:07 PM EST
Impossible to determine.

One might survive a point blank shot (I know of one MEDEVAC conducted in which px took 2x7.62x39 to torso at very close range and lived due to some heroic medics/pilots).

Or you might get dropped by that 1:1,000,000 shot that was shot into the air 1,000m away.

How'd the 5.56 thread go?
MichigamaGunslinger  [Team Member]
8/19/2010 9:11:59 PM EST

Originally Posted By KILLERB6:
Impossible to determine.

One might survive a point blank shot (I know of one MEDEVAC conducted in which px took 2x7.62x39 to torso at very close range and lived due to some heroic medics/pilots).

Or you might get dropped by that 1:1,000,000 shot that was shot into the air 1,000m away.

How'd the 5.56 thread go?
Lol, it went pretty much as expected. It did give me a better idea as to range, I am pretty sure I will either get an AK in 7.62x39 or maybe build up an AR marked "multi-cal", buy a basic BCM upper in 5.56mm and wait to see if 6.5 or 6.8 SPC catches on enough to become a mainstream military cartridge like 5.56mm. Maybe just get both, that seems to be the popular solution here...

KILLERB6  [Team Member]
8/20/2010 12:35:29 AM EST
5.56 works just fine...so does 7.62(x39) at any range you have any business shooting someone at under normal (combat) circumstances, except for a DMR or sniper...then their job is to reach out and touch someone.

I like the 6.8 quite a bit, but am sort of regretting the move as a 308 like the LMT or REPR seems a lot more practical, albeit more expensive upfront. I don't think the 6.8 will ever be THE military small arms cartridge the 556 is...not anytime soon, just my opinion.

There are a couple of ballistic studies out that put the 6.8's close to midrange lethality above 556 (of course) AND 7.62 (surprisingly to some). Eventually the 7.62 wins out at extreme range.
Zhukov  [Moderator]
8/20/2010 6:16:23 AM EST
The same answer applies as in the AR ammo forum, but virtually NONE of the 7.62x39 projectiles fragment to begin with. The lethality in this case is dependent almost entirely on your shot placement.
KILLERB6  [Team Member]
8/20/2010 7:10:27 AM EST
Originally Posted By Zhukov:
The same answer applies as in the AR ammo forum, but virtually NONE of the 7.62x39 projectiles fragment to begin with. The lethality in this case is dependent almost entirely on your shot placement.


Doesn't it always?

This is my answer to the "the .mil needs a more lethal round"...you have to hit them first...then we'll talk lethality or lack thereof.
ravinluna  [Member]
8/20/2010 12:50:00 PM EST
I was in the pit at a local HP match, the guy shooting an SKS at 800 yards had his bullets going sideways thru the target at a very steep angle.
Crito  [Member]
9/1/2010 8:46:20 PM EST
Originally Posted By KILLERB6:
Originally Posted By Zhukov:
The same answer applies as in the AR ammo forum, but virtually NONE of the 7.62x39 projectiles fragment to begin with. The lethality in this case is dependent almost entirely on your shot placement.


Doesn't it always?

This is my answer to the "the .mil needs a more lethal round"...you have to hit them first...then we'll talk lethality or lack thereof.


Lethal rounds are frowned apon by NATO. The reason they use FMJ and why the army's pistols suck (no HP).
stainlessAR15shooter  [Member]
9/2/2010 3:21:24 AM EST
Originally Posted By Crito:
Originally Posted By KILLERB6:
Originally Posted By Zhukov:
The same answer applies as in the AR ammo forum, but virtually NONE of the 7.62x39 projectiles fragment to begin with. The lethality in this case is dependent almost entirely on your shot placement.


Doesn't it always?

This is my answer to the "the .mil needs a more lethal round"...you have to hit them first...then we'll talk lethality or lack thereof.


Lethal rounds are frowned apon by NATO. The reason they use FMJ and why the army's pistols suck (no HP).


I might be wrong but I think Int'l law specifically the Hague convention of 1899 is why militaries around the world use only FMJ bullets not fragmenting or expanding rounds. What NATO wants or doesn't want has nothing to do with it.
Crito  [Member]
9/2/2010 2:23:24 PM EST
Originally Posted By stainlessAR15shooter:
Originally Posted By Crito:
Originally Posted By KILLERB6:
Originally Posted By Zhukov:
The same answer applies as in the AR ammo forum, but virtually NONE of the 7.62x39 projectiles fragment to begin with. The lethality in this case is dependent almost entirely on your shot placement.


Doesn't it always?

This is my answer to the "the .mil needs a more lethal round"...you have to hit them first...then we'll talk lethality or lack thereof.


Lethal rounds are frowned apon by NATO. The reason they use FMJ and why the army's pistols suck (no HP).


I might be wrong but I think Int'l law specifically the Hague convention of 1899 is why militaries around the world use only FMJ bullets not fragmenting or expanding rounds. What NATO wants or doesn't want has nothing to do with it.


Thats true..
jaholder1971  [Team Member]
9/8/2010 6:52:54 PM EST
The round is lethal at any distance that it is moving, how about that
45-Seventy  [Member]
9/19/2010 2:00:03 PM EST
Originally Posted By ravinluna:
I was in the pit at a local HP match, the guy shooting an SKS at 800 yards had his bullets going sideways thru the target at a very steep angle.


The fact that his rounds were hitting the target (sideways or not) is impressive enough with an SKS at 800 yards. Good on'em!
J_C  [Member]
9/20/2010 8:48:47 AM EST
It depends on the load and bullet but in general you can expect at 500 yards you still have plenty energy to be lethal (350-400 ft/lbs). The problem is you've also got about 7 feet of bullet drop at this range. I cannot really imagine how anyone is hitting a target at 800M, that is pretty good shooting.

I find this site pretty helpful for comparing ballistics of different cartridges: http://www.rifleshootermag.com/ballistics/762_39mm_russian.html
SGTDUSMC  [Member]
9/20/2010 6:45:29 PM EST
I belive that beyound the range that the 5.56 will no longer fragment ( aprox. 2,500 fps and 2,700 fps) the 762 x 39 will be more leathal. The sks at 800 yds (if the barrel is up to spec.) will lose accracy when it changes from supersonic to subsonic. This is actually the same force that distrubs aircraft entering or leaving the speed of sound. It is caused by the various portions of the bullet depending on their shape going through the sound barrier up or down at different speeds. such as air passing over a slanted serface of the bullet faster than air passing over a flat portion. so the speed of sound is happening at different parts of the same bullet at the same volicity thus detering its flight.


he went into younder village and never returned
countryrebel  [Member]
10/4/2010 6:44:02 AM EST
I would think if you were hit by a 7.62x39 way out there you are going to be out of the fight or not much good anyway. So to the op, we have shot deer over 500 yards with that round and had no problems. I do not go (by the numbers), I go by what I have seen. Hope this helps.
elokoman  [Member]
10/5/2010 6:59:39 PM EST
"I belive that beyound the range that the 5.56 will no longer fragment ( aprox. 2,500 fps and 2,700 fps) the 762 x 39 will be more leathal."....What he said, except "lethal"

because it seems like the Russian bullets would have an advantage in their yawing and tumbling tendency beyond the frag range of the standard issue 5.56 bullets, but I am not an expert in this. So if I am correct, it is somewhat of a tradeoff, one significantly better at closer ranges, the other somewhat better at longer ranges, and yes, shot placement absolutely a paramount factor in outcome. Is the 7.62 x39 going to be as accurate as 5.56 at longer ranges and enable equal placement capability? doubtful, The 5.45 might come a lot closer in skilled hands.

Seems like your choice might depend on how much cover the terrain offers. If you are in open country, you might have more long range shots, in which case the Russian bullets may have an advantage. In brushy country, I would opt for 5.56.

Personally, I don't anticipate anything long range for self defense, it is brushy around here. That does not mean I am knockin' 7.62x39, it has it's strong points. I would tend to grab the 5.56 first if under some type of life threatening situation, given a choice of one or the other, to each his own. I do like the reliability of the AK.
BroncoMafia  [Member]
10/11/2010 12:19:02 PM EST
Comparing lethality of a bullet only without considering the inherent strengths and weakness of the launching platform is foolhardy.
The accuracy potential of the AR platform is in a whole different universe than that of the AK platform.
Sight radius and type with irons, optics mounting options, free floated barrel, DI vs Piston, much better barrels.
The AR platform destroys the AK in accuracy potential.

The ballistics or each round then come in to play.
Assuming Hornady's new round is similar (if not better) than most mil spec 7.62x39

Velocity (fps) / Energy (ft-lbs)
Muzzle 100 200 300 400 500
2350/1508 2040/1136 1755/841 1502/616 1289/454 1129/348
Trajectory (inches)
Muzzle 100 200 300 400 500
-1.50 3.50 0.00 -14.80 -45.20 -96.60


Ballistic coefficient of .260, meaning is slows and drops MUCH faster than the 75 grain TAP round, which spots a BC of .395
Hornady LE website
At 500 yards, the 5.56 has dropped only half as far as the 7.62x39 (46 inches of drop instead of 96 inches), increasing the chance of a hit significantly.


Velocity (fps) / Energy (ft-lbs)
Muzzle 500 yards
2790/1296 1757/514
Trajectory (inches)
500 yards
-49.3
elokoman  [Member]
10/14/2010 7:05:12 AM EST
Not so sure that I agree that bullet drop is the deciding factor in ability to hit or not, that would depend on the range, because the sights or the optics adjustments can compensate for that drop. If we are talking about sniper range, yes, bullet drop is quite important, but then we should be looking at .308 or maybe .300 Win Mag or .338. But as you pointed out, other factors in the AR platform do make it inherently more accurate at range than the AK platform, and thus more likely to obtain good shot placement. Correct me if I am wrong, but beyond frag range, the better 7.62x39 bulllets such as M67 and the 5.45 x39 bullets have a better tendency to tumble than standard issue 5.56 bullets, which should make them more lethal at ranges of say between 200 and perhaps 500 yards if the shot placement is right. Now if we are talking about the best 5.56 loads compared to Eastern bloc ammo, it is another story, but there is a huge cost difference for the average Joe. My interest is self defense, not military sniping, so the 5.56 seems the way to go. Yet as noted earlier, the incredible reliability of the AK platform makes me respect it.
BroncoMafia  [Member]
10/19/2010 8:10:18 AM EST
Good logic elokoman.
5.56, 7.62x39 or 5.45x39, they all tumble (the base of the bullet is much heavier than the tip and it flips almost instantly when it encounters flesh).
The difference is that the 5.56 will fragment when it begins to yaw if it is traveling fast enough. The 7.62x39 or 5.45x39 will NOT frag.
In other words, at long ranges, the 5.56 is equal to 5.45. at close range, it is far superior.


TexasRifleman1985  [Team Member]
11/2/2010 10:13:03 PM EST
Originally Posted By BroncoMafia:
Good logic elokoman.
5.56, 7.62x39 or 5.45x39, they all tumble (the base of the bullet is much heavier than the tip and it flips almost instantly when it encounters flesh).
The difference is that the 5.56 will fragment when it begins to yaw if it is traveling fast enough. The 7.62x39 or 5.45x39 will NOT frag.
In other words, at long ranges, the 5.56 is equal to 5.45. at close range, it is far superior.




Yaw is the word you are looking for, not tumble. The bullet attempts to change its heading 180 degrees in a fluid medium. Tumbling implies it will continue to rotate after that, when generally it will not.


To the OP: The difference in lethality made by switching between 7.62x39 and 5.56x45 pales in comparison to the difference in lethality between a truly skilled shooter and you typical American black-gun owner. A man well trained and practiced with either platform should be treated with equal respect for potential lethality.

A skilled rifleman with an AK has a surprisingly good chance of dropping you even at ridiculus distances that mortals wouldn dismiss as impossible. Remember that.

TR85.
chowchow  [Member]
11/3/2010 4:09:41 PM EST
Within 300 meters is what it was designed to do .
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