Accuracy Limit of the 7.62X39 Cartridge

[rg1911]

Has anyone determined what is the absolute best consistent accuracy that can be wrung from the 7.62X39 cartridge? For instance, the AK47 is designed to be a roughly 4-MOA rifle. What could the cartridge achieve in a good bolt action rifle?

A similar question could be asked of other .30 caliber cartridges, such as the .30 Carbine and the 7.62X25 Tokarev cartridges. Like the 7.62X39, neither cartridge normally is chambered in a firearm designed for pinpoint accuracy.

Thank you,
Richard

 

[...]

guys over at rifle shooter built a custom remington 700 chambered in 7.62x39, and were getting sub MOA out of steel cased Brown Bear.

http://rifleshooter.com/2016/03/building-a-remington-700-in-7-62x39-mm-russian/

 

[rg1911]

guys over at rifle shooter built a custom remington 700 chambered in 7.62x39, and were getting sub MOA out of steel cased Brown Bear.

http://rifleshooter.com/2016/03/building-a-remington-700-in-7-62x39-mm-russian/

Wow! That's one heck of a project. Looks like the 7.63X39 does exhibit good potential accuracy. (Next stop, the sub-MOA AK-47. Or perhaps not.)

And thank you for pointing me to that site.

Cheers,
Richard

 

[evans1010]

I always assumed that the accuracy limitation of x39 rifles had more to do with the quality/consistency of most ammo in the market than the rifle itself.

AK's may not be the best example of this but I personally feel that it's this ammo limiting factor that has kept people from building in more accurate platforms.

Sent from my XT1585 using Tapatalk

 

[supercorndogs]

The 7.62x39 can be just as accurate as any other cartridge. Its big limiter is velocity.

 

[Sooter76]

(Next stop, the sub-MOA AK-47. Or perhaps not.)

Already been done...

 

[rg1911]

Already been done...

Do you have any information?

Thanks,
Richard

 

[hollowoutadime]

I suppose they could be accurate...however..
For the average AK/SKS shooter, there's probably a tendency to shoot factory ammo. I can't buy components for what they sell boxed rounds for. I did an small, informal reloading class - probably loading 6.5 cm or .260 - the usual - using a modified case. an RCBS measure to ,1 grain, Berger or Sierra bullets. Decided to take a break and pull some Wolf and TulAmmo cartridges apart and measure the components. Bullets were 0.5 grains (or more off), powder weight was as bad or worse. Both brands were pretty bad. To be fair, I'm guessing that the buyer (of those) isn't expecting precision and is probably shooting at 50-150 yards where, at some point, they will hit the TV set or watermelon.

 

[JMcBurn]

I suppose they could be accurate...however..
For the average AK/SKS shooter, there's probably a tendency to shoot factory ammo. I can't buy components for what they sell boxed rounds for. I did an small, informal reloading class - probably loading 6.5 cm or .260 - the usual - using a modified case. an RCBS measure to ,1 grain, Berger or Sierra bullets. Decided to take a break and pull some Wolf and TulAmmo cartridges apart and measure the components. Bullets were 0.5 grains (or more off), powder weight was as bad or worse. Both brands were pretty bad. To be fair, I'm guessing that the buyer (of those) isn't expecting precision and is probably shooting at 50-150 yards where, at some point, they will hit the TV set or watermelon.

Why not pull the bullets and re drop the powder? Russian primers are usually super consistent.

 

[schmi015]

I think most rounds are inherently accurate when powder charges have the lowest variance. Ak ammo is typically fired out of a gun with loose tolerances so it can function in muddy trenches and prolonged periods without maintenance. That wolf, bear etc is still capable of hitting man sized targets out to 200-300 pretty easy even with .5 grains off. The .220 Russian, 6mm ppc, 6.5 grendel share a similar lineage being derived from 7.62x39 and those are all "accurate cartridges." I would think that with new hornady or lapua brass in a bolt gun with match bullets you could get half moa groups out to 300yds.

 

[hollowoutadime]

Why not pull the bullets and re drop the powder? Russian primers are usually super consistent.

You could redrop the powder - but then you need to weigh and sort bullets That assumes that the bullets and jackets are somewhat uniform in construction. Since they are usually semi-auto you might want to re-crimp everything. Some of that is steel case which may or may not recrimp well. When you're done, you would probably want to re-barrel from the ChiCom barrel. For that effort, I might as well put the labor into my 6.5 or 260 and have a known good shooter.

A long, long, time ago I used to shoot Ohio groundhogs on farm fields with that round. This was before electronic rangefinders. That heavier round with light powder drops pretty quickly, so you really had to range them well.

 

[Doubs]

As most likely know already, the 7.62x39 was developed from the 8x33 Kurtz round fielded by the Germans against the Russians in WW2. The Germans realized that most combat took place within 300 meters so cartridges effective beyond that distance were a waste of materials. The Russians quickly realized that fact and thus the 7.62x39mm cartridge chambered in the SKS rifle was fielded.

Below is a 3 shot group from my AR in 7.62x39 at 100 yards using a 3X optic. I used my reloads with cheap 123 grain soft point bullets. The cartridge can be accurate given some care in loading it.

 

[rg1911]

Concerning the Soviet cartridge being based on the German 7.92X33mm cartridge, I found this side-note in an article by Peter J. Kokalis, who people seem to either love or hate. You may take this information for what it's worth:

"Attributed to designers Nikolai M. Elizarov and Boris V. Semin, Soviet historians contend that work on the M43 (model 1943) 7.62X39mm cartridge began in 1939, was temporarily suspended because of The Great Patriotic War and then re-commenced and finalized in 1943. Others have stated that it was derived from the German 7.92X33mm Kurz Patrone (short cartridge) developed for the world's first assault rifle produced in significant quantities, the World War II MP43/44 (StG44/45). This latter scenario is highly unlikely, as the Soviets would have required specimens of 7.92X33mm Kurz ammunition at least a year or two prior to their adoption of of the 7.62X39mm round in 1943 -- well before the MP43 was fielded on the Osten front (first reported use was December 1942). Whatever the case, the Soviet M43 cartridge is a true intermediate-size assault rifle round. First prototypes featured cases 40.29mm in length (thus: 7.62X41mm). The case was trimmed to 38.6mm as the original projectile proved unsatisfactory and a new bullet was adopted that required a shorter case."

Cheers,
Richard

 

[Doubs]

Concerning the Soviet cartridge being based on the German 7.92X33mm cartridge, I found this side-note in an article by Peter J. Kokalis, who people seem to either love or hate. You may take this information for what it's worth:

"Attributed to designers Nikolai M. Elizarov and Boris V. Semin, Soviet historians contend that work on the M43 (model 1943) 7.62X39mm cartridge began in 1939, was temporarily suspended because of The Great Patriotic War and then re-commenced and finalized in 1943. Others have stated that it was derived from the German 7.92X33mm Kurz Patrone (short cartridge) developed for the world's first assault rifle produced in significant quantities, the World War II MP43/44 (StG44/45). This latter scenario is highly unlikely, as the Soviets would have required specimens of 7.92X33mm Kurz ammunition at least a year or two prior to their adoption of of the 7.62X39mm round in 1943 -- well before the MP43 was fielded on the Osten front (first reported use was December 1942). Whatever the case, the Soviet M43 cartridge is a true intermediate-size assault rifle round. First prototypes featured cases 40.29mm in length (thus: 7.62X41mm). The case was trimmed to 38.6mm as the original projectile proved unsatisfactory and a new bullet was adopted that required a shorter case."

Cheers,
Richard

Mr. Kokalis' explanation is plausible. It's also possible that through their spies the Soviets were aware of the 8x33mm cartridge well before it's introduction to the battlefield. Considering the secrecy that the Soviets exercised WRT weapons development, we may never know the full story behind the cartridge. There is no disputing that it has become one of the world's great cartridges.

 

[Greg Langelius *]

I've been doing some intermittent load development for my Savage 10FCM Scout 7.62x39 over the past decade or so. This rifle uses a nominally .308" diameter bore with a common choke bore to accommodate both .30 caliber and .303 caliber bullets.

When attention is paid to detail, I find that handloads can be, as suggested above, as accurate as any other chambering. The Savage 7.62x39 FCM Scout is out of production, and the current Model 11 based Scout is not offered in 7.62x39. My own 10FCM Scout certainly appears to have a good accuracy potential. Until load development is further along with the 110GMX, I'll not be getting specific about groups, but I heartily recommend the effort. 110 V-Max loads shot sub MOA.

My basic strategy has been to use lighter than military weight bullets (I use Hornady 110gr V-Max and GMX bullets) for a flatter trajectory, near-listed-max charges of IMR-4198, and Hornady makes decent brass that employs small rifle primer pockets. Care should be taken with the GMX projectile to start with low charge weights, as the solid copper bullet composition can generate higher pressures.

Accuracy should come as no surprise, as the PPC cartridges, the .220 Russian, and the 7.62x39 share nearly identical parent cases. For something even closer to home, research the .30PPC.

After a protracted detour into the .30BR, I have reverted to the 7.62x39 as a lower energy cartridge based accuracy project. I have an irrational preference for a bolt guns that share the chambering of semi's in my collection, and the Savage 10FCM Scout appears to me as having a high potential to be one of these complementing my Yugo SKS.

Aside from the significant case taper, I would prefer this 7.62x39 over the .30AAC, and/or the .30AR. I would be extremely interested in seeing a .30 caliber wildcat based on the .22 Nosler. I think it could provide a fairly energetic small package .30 caliber chambering.

Greg

 

[sav338lapua]

Over the years I have always owned an AK but way back when bought a carbine AR-15 in 7.62X39. I used it to take 4 whitetails at 60 to 125 yards.
With winchester ammo (123gr soft points) it was very accurate and avg 2325 FPS.
I use my AK-47 now it's taken 10 whitetails too. But my PTR 32 is very very accurate even shooting the cheapest stuff into 1.5-2 inch groups at times,
but with the good stuff it holds an inch sometimes even a little under.
I trick we used in service rifle high power to get the maximum accuracy from our rifles with handloads is to set your resizing die high then run a case thru the die and then try to chamber it in your rifle. Then screw the die down some more and try to chamber it again. You do this until the brass just chambers easily. Lock it in place. Now you have brass that's as close to "0" headspace as possible but will still chamber properly.
Hey before I go though check out the Czech 7.62X45. It's the same bullet as the 7.62X39 but 200 to 250 FPS faster!!!
SB

 

[rg1911]

My basic strategy has been to use lighter than military weight bullets (I use Hornady 110gr V-Max and GMX bullets) for a flatter trajectory, near-listed-max charges of IMR-4198, and Hornady makes decent brass that employs small rifle primer pockets. Care should be taken with the GMX projectile to start with low charge weights, as the solid copper bullet composition can generate higher pressures.
Greg

Interesting thought about trying lighter-weight bullets. I have some of the Hornady 110-gr V-Max that I was trying in my M1 Carbines (single loaded due to length); shall see what happens in my AK and my SKS. (The AK can't possibly get worse than its current 4-MOA using junk ammo, careful handloads, Lapua and Norma factory, etc. Gotta give it an "A" for consistency.) I may even have some IMR 4198 hiding in the woodpile to try in place of the Reloder 7.

One of these days I'm going to find an AK that's at least consistently 2-MOA and buy it.

Cheers,
Richard

 

[Greg Langelius *]

My near max load with the 110gr GMX/V-MAX is 26.5gr of IMR-4198. It works in my own rifle, but may be overly peppy for the COMBLOC rifles. Pressure signs indicate a moderate working pressure. I consider it too premature to sign off on my current load testing results.

The current Hornady manual lists a max of 26.6gr of IMR-4198 in a test rifle described only as an SKS.

Greg

 

[Coltster]

Dave Lauck recently released a full custom hybrid Type AK, like the rest of DL Sports stuff I'm sure it's pretty impressive. http://www.dlsports.com/dl-2015-carbine.html

i have a Krebs KV-13 that I really like, have not tested for accuracy potential but am pretty confident it would be way more accurate than most. Especially if good brass ammo is used like Lapua.

 

[TorF]

About 30 years ago I had a factory Sako Vixen chambered for 7.62x39. The factory barrel was.311 and it shot sub moa with Sako fmj military ammo. Handloads with proper 311 bullets shot . 5moa.

 

[Sooter76]

Do you have any information?

Thanks,
Richard

Nothing specific I can remember off the top of my head. I just know several people, including Rifle Dynamics, have done so. I think MAC may have even done a video on one effort. The problem isn't that it can't be done, the problem is that when Bubba wants a $500 bullet bullet hose it isn't cost money effective to invest the time, money, and effort.

 

[BarrettBoy]

Theoretically with a good handload and tuned rifle I don't see why it can't be sub moa at 100 yards.
It's just when you take it to medium/long distances, the aerodynamics of the 7.62x39 projectile suffers.

Personally, tula out of my Zastava never gets better than 3moa.