Ballistics - Involving the AK

[S-Lee]

And how much would that "delicious piece of pastry chef masterpiece" cost us mere mortals with mortgages, etc.

I know all about the "what is your life worth" discussion, but a line must be drawn somewhere...after all, if we do not put a price tag on it, why not simply hire a three man operator cell made up of former Spetsnaz, Delta types to follow you around for the rest of your life.

It would costly, yes...but what is your life worth? Not trying to be contentious, just practical.;)

My life is worth a lot.. so I am not afraid to spend money on proven qual;ity items....AK might be cheaper, but i shoot much better with the AR system, so within my budget, the AR system is a good deal.. :) so what is practical... 14.5mm in 6.8mm off an AR system, or if i can get my hands on the SCAR.

as far as price.. FN SCAR will cost on more then 1k, which is what a good AK cost nowadays from a company like Krebs. SCAR retain all the great egronomics of the AR system and the added reliability of a high tech construction and gas piston system.

if you have to build a gas gun from scratch...
standard LMT M4 carbine is about 8-900 dollars complete.
a good LWRC conversion is about 600.00.
6.8 magazines are about 40 dollars each.

not exact cheap but it is not a bad price for the best CQB to mid range setup.

[Section1_Operations]

That right there is issue. What we are loading with now - AR & AK - is not what was studied in Vietnam.

Hopefully, the information I’ve provided can delineate the differences better for you.

I'm no ballistics expert, but I keep hearing about 7.62X39 simply punching holes in people and not tumbling. My impression was that penetration was a much more significant issue in it's design than yawing was.

Correct, both Fackler and Robert’s information suggests that most current lead core 7.62x39 FMJ provides a similar permanent wound no better than a 9mm FMJ.

This subject also brings up the issue of just what AR round are we talking about?

See my information…

One person has mentioned the heavier bullets. If I understand things correctly, they are actually doing worse as fight stoppes because they are moving more slowly, but mostly because they are so stable that the aren't having the tumbling effect that the lighter, less stable bullets have. From a military aspect, there are advantages to a heavier, more stable bullet, but for us civilians working in an urban environment, what we want is instability.

Please cite the source for the information in Red as it is not correct in terms of the OTM designed projectiles. In term of the M855 it’s a velocity and barrel equation as it pertains to the engaged distance of the target.

Also, flight stability of the projectile has nothing to do with its wounding ability. That’s determined by the projectile design and whether the projectile hits the target within its operating velocity window to inflict the maximum wound damage.

One reason so many raid teams are going to 5.56 is the over penetration issue (when compared to pistol calibers). We shouldn't pick a cartridge just because of what will happen if we miss, but it is part of the overall equation.

Having said all that, round for round, the AK certainly has the potential to be a better stopper. I do question whether that potential has been realized to much extent, certainly not to extent it has been with the 5.56 simply due to virtually zero evolution on one hand and decades of change, testing, and tweaking on the other.

The AR works and I would even go so far as to say it is a good choice despite what it's chambered for. And, the AK is a good choice despite, or because, it's design hasn't changed much. Both do the job, and picking one over the other really shouldn't come down to terminal ballistics in a general sense. We can create scenerios for each one in which it would be a better choice than the other, but that is just gaming.

Domestically produced 7.62x39 is finally being tweak and tested with new bullets to offer better performing loads. Dr. Robert’s was supposed to have conduct some recent gelatin testing and I expect to see some of that data from the 7.62x39 loads like Corbon, etc. soon. (When I find them I’ll post them)

[Section1_Operations]

if you have to build a gas gun from scratch...
standard LMT M4 carbine is about 8-900 dollars complete.
a good LWRC conversion is about 600.00.
6.8 magazines are about 40 dollars each.

not exact cheap but it is not a bad price for the best CQB to mid range setup.

Complete LW 6.8 rifle = $1,450
6.8 C Product SS Mags= $26 each

IMO, converting an upper at this point in time for $600 isn't worth the added cost when it's compared to a completely NEW upper. For LE agencies on a budget it's a viable upgrade to save money.

[Gabe Suarez]

The original 7.62 x 39 mm Russian M43 Type PS 120.5 gr FMJ boat-tail bullet has a copper-plated steel jacket covering a large steel core. The predominant feature of this cartridge is the MINIMAL amount of damage it produces in soft tissue wounds, on par with FMJ handgun wounds such as those produced by 9 mm M882 ball.

I don't think anyone is using Russian M43, nor can anyone even buy it here in CONUS.

However, not all 7.62 x 39 mm FMJ bullets are of the original steel core construction. Significantly increased tissue damage is produced by the early yaw seen with several 7.62 x 39 mm FMJ lead core bullets, including:

-- Yugoslavian M67 124 gr FMJ, flat based, copper-jacketed, lead core bullet which travels only 3.5" in tissue before yawing

-- Chinese (PRC) 7.62 x 39 mm 123 gr FMJ, copper-jacketed, lead core bullets which begin their yaw after only 2-2.5" of travel in tissue.

-- Czech and several types of Western commercially produced lead core 7.62 x 39 mm FMJ yaw within the first 2-3” of travel in tissue.

All of the commercially available 7.62 ammo today is lead core.

In both uncomplicated extremity and torso wounds, the very early yaw of these lead core 7.62 x 39 mm FMJ bullets allow the projectiles to travel sideways through the body, increasing permanent tissue destruction and temporary cavitation effects compared to the standard 7.62 x 39 mm Russian M43 Type PS 120.5 gr FMJ. These early yawing lead core 7.62 x 39 mm FMJ bullets cause wounds very similar to the 5.45 x 39 mm Russian M74 53 gr FMJ bullets.

Originally Posted by DocGKR - On 7.62x39 Yaw

There is no standard answer as to if and when a 7.62 x 39 mm bullet will yaw. With the original Soviet M43 Type PS 120.5 gr steel core FMJ, the bullet tends to drill right through the average human torso without yawing or fragmenting, resulting in relatively minor wounds as long as no critical structures are directly struck by the bullet--this bullet eventually exhibits a bi-lobed yaw cycle as depicted in the first wound profile above.

See above.

The lead core 7.62 x 39 mm, such as the Yugoslavian M67, PRC lead core and American commercial lead core 123 gr FMJ’s begin to yaw after only 2-4" of travel in tissue, causing significantly greater permanent and temporary cavity effects, similar to those caused by the 5.45 x 39 mm M74 53 gr FMJ bullets fired by the AK74 as depicted in the second WP above.

So has the ammo that is available today been tested? The ammo we can buy seems at least the same type as the Winchester soft points.

In a CQB setting, the 6.8 mm OTM and PT will fragment and are unlikely to exit the torso; the 7.62x39 mm SP's tend to retain their mass and are very likely to exit target. Both will work, although I would prefer the 6.8 mm for this settting. I am looking forward to trying the 7.62x39 mm PT later this month to see if it will be a viable choice for CQB.

OK, but few normal people will be ready to spend a grand and a half for a wildcat cartdridge when other options are available.

[Gabe Suarez]

I would like to see an independant test by an non-involved party (someone like Ammo Lab) on the various loadings of 7.62x39mm.

[Drifting Fate]

Hopefully, the information I’ve provided can delineate the differences better for you.






Please cite the source for the information in Red as it is not correct in terms of the OTM designed projectiles. In term of the M855 it’s a velocity and barrel equation as it pertains to the engaged distance of the target.

First, thank you for taking the time to post all of that information in one spot. There's a lot of good stuff there that I want to go back and spend more time studying when I get the chance.

Second, the source for my information is obviously not as good as yours, so it's probably a moot point. I can't even remember the specifics - some gun book or magazine I should have known better than to read in the first place. I stand corrected and am always happy to be so - much better to have the right information than go along believing the wrong information.

I look forward to reading any more information you care to share about this subject.

[Section1_Operations]

I would like to see an independant test by an non-involved party (someone like Ammo Lab) on the various loadings of 7.62x39mm.

Gabe-

FYI, Dr. Robert's posts were taken as is so the 6.8 SPC is a moot issue here. (I don't need to go to a 6.8 SPC to get great penetration.)

I agree that a specific testing session for just 7.62x39 rounds would be most helpful for not only our WT community but the greater ballistics library of information.

Maybe David (AmmoLab) can give us a cost per round tested number and we can pull the funds to have him run the tests if he has the time, and willingness to conduct them.

IIRC, the surplus Chinese steel core 7.62x39 ammo is no longer available for importation into the U.S.; however, there is surplus 5.45x39 available and other non-Chinese 7.62x39 steel core that is available for import.

[motley1]

AL,
The round I was talking about is the Winchester Ranger 55gr ballistic silver tip. If you look at permanent cavity, versus temporary cavity disruption that is where you see the difference. The reason a FMJ bullet causes so little damage is because the human body is so elastic. The bullet can spin, yaw and twist, it does not make a difference. Even someone shot in the heart can still fight for a short period of time. Organs are elastic as well. You need the round to fragment and stay in the body. The more the bullet fragments the greater the permanent wound cavity it will cause. Those little fragments are like little razors cutting everything in its path. It applies to head shot trauma to the brain and CNS as well.
Just because a round might leave a big exit wound as it leaves the body, the bad guy then has to bleed out and can still fight. The job needs to take place in the body to shut someone down the quickest. Those of us who are not currently in the military are lucky because we get to choose the round that we want to protect our families and persons with. We can throw a million variables into the situation such as shooting into a vehicles windshield, types of body armor, barrier penetration if the bad guy has fortified his position. I then would want a FMJ or bonded bullet of a larger caliber to make sure the rounds make into the body. I just thank God that we live in a Country where we have the right to carry guns and we can have a friendly debate over the ammo we put in them. Guys get to bent out of shape over the I"m right your wrong aspect of things. The bottom line is to train and stay hard!!!!!!!! The wolf could come knocking at your door tonight.

Shawn

[Section1_Operations]

The original 7.62 x 39 mm Russian M43 Type PS 120.5 gr FMJ boat-tail bullet has a copper-plated steel jacket covering a large steel core. The predominant feature of this cartridge is the MINIMAL amount of damage it produces in soft tissue wounds, on par with FMJ handgun wounds such as those produced by 9 mm M882 ball.


I don't think anyone is using Russian M43, nor can anyone even buy it here in CONUS.

This information is simply to cover the full spectrum of ammo development - not start a vs. debate.

However, not all 7.62 x 39 mm FMJ bullets are of the original steel core construction. Significantly increased tissue damage is produced by the early yaw seen with several 7.62 x 39 mm FMJ lead core bullets, including:

-- Yugoslavian M67 124 gr FMJ, flat based, copper-jacketed, lead core bullet which travels only 3.5" in tissue before yawing

-- Chinese (PRC) 7.62 x 39 mm 123 gr FMJ, copper-jacketed, lead core bullets which begin their yaw after only 2-2.5" of travel in tissue.

-- Czech and several types of Western commercially produced lead core 7.62 x 39 mm FMJ yaw within the first 2-3” of travel in tissue.


All of the commercially available 7.62 ammo today is lead core.

Yes, the domestically produced ammo is as well as most of the Wolf, Brown/Silver Bear etc.. (Steel core military surplus is still out there, and at one time the Brown or Silver bear brand used a Zinc/Steel core copper washed projectile.)

In both uncomplicated extremity and torso wounds, the very early yaw of these lead core 7.62 x 39 mm FMJ bullets allow the projectiles to travel sideways through the body, increasing permanent tissue destruction and temporary cavitation effects compared to the standard 7.62 x 39 mm Russian M43 Type PS 120.5 gr FMJ. These early yawing lead core 7.62 x 39 mm FMJ bullets cause wounds very similar to the 5.45 x 39 mm Russian M74 53 gr FMJ bullets.


Originally Posted by DocGKR - On 7.62x39 Yaw

There is no standard answer as to if and when a 7.62 x 39 mm bullet will yaw. With the original Soviet M43 Type PS 120.5 gr steel core FMJ, the bullet tends to drill right through the average human torso without yawing or fragmenting, resulting in relatively minor wounds as long as no critical structures are directly struck by the bullet--this bullet eventually exhibits a bi-lobed yaw cycle as depicted in the first wound profile above.


See above.


The lead core 7.62 x 39 mm, such as the Yugoslavian M67, PRC lead core and American commercial lead core 123 gr FMJ’s begin to yaw after only 2-4" of travel in tissue, causing significantly greater permanent and temporary cavity effects, similar to those caused by the 5.45 x 39 mm M74 53 gr FMJ bullets fired by the AK74 as depicted in the second WP above.


So has the ammo that is available today been tested? The ammo we can buy seems at least the same type as the Winchester soft points.

Some have but some has not. FMJ will likely perform as Dr. Robert's last quote above indicates and the JSP's for the 7.62x39 act similarly to the .30-30 JSP's.

In a CQB setting, the 6.8 mm OTM and PT will fragment and are unlikely to exit the torso; the 7.62x39 mm SP's tend to retain their mass and are very likely to exit target. Both will work, although I would prefer the 6.8 mm for this settting. I am looking forward to trying the 7.62x39 mm PT later this month to see if it will be a viable choice for CQB.


OK, but few normal people will be ready to spend a grand and a half for a wildcat cartdridge when other options are available.

Simply a comparison and not a statement included to start a vs. debate on anything.

[Section1_Operations]

AL,
The round I was talking about is the Winchester Ranger 55gr ballistic silver tip. If you look at permanent cavity, versus temporary cavity disruption that is where you see the difference. The reason a FMJ bullet causes so little damage is because the human body is so elastic. The bullet can spin, yaw and twist, it does not make a difference. Even someone shot in the heart can still fight for a short period of time. Organs are elastic as well. You need the round to fragment and stay in the body. The more the bullet fragments the greater the permanent wound cavity it will cause. Those little fragments are like little razors cutting everything in its path. It applies to head shot trauma to the brain and CNS as well.
Just because a round might leave a big exit wound as it leaves the body, the bad guy then has to bleed out and can still fight. The job needs to take place in the body to shut someone down the quickest. Those of us who are not currently in the military are lucky because we get to choose the round that we want to protect our families and persons with. We can throw a million variables into the situation such as shooting into a vehicles windshield, types of body armor, barrier penetration if the bad guy has fortified his position. I then would want a FMJ or bonded bullet of a larger caliber to make sure the rounds make into the body. I just thank God that we live in a Country where we have the right to carry guns and we can have a friendly debate over the ammo we put in them. Guys get to bent out of shape over the I"m right your wrong aspect of things. The bottom line is to train and stay hard!!!!!!!! The wolf could come knocking at your door tonight.

Shawn

.223 Rem. 50gr. JSP


Hornady 55gr. TAP


.223 Federal TRU 64gr. JSP


Hornady 60gr. JSP