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6.8mm Remington SPC II conversion


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If you wanted to convert a Saiga into a different caliber, the 6.8mm Remington SPC cartridge, what bolt would be best? I am thinking, that from the dimensions of the 6.8mm round that the .223 would probably work best, just take the extractor out and have a machine shop open it up slightly to the 6.8mm brass head dimension, and fine tune the extractor for good fit. You would have to get a new barrel and have it fitted for headspace, of course. And, I think the existing bolt carrier would not need modifications.

 

However, the magazine holding the 6.8mm SPC might be the real bear in this equation. It's one thing to re-chamber a bolt action round, especially a single shot from one caliber to the next, but it's a different situation when you have a semi-automatic to deal with. Would the need of an AR adapter with use of AR 6.8mm SPC magazines be the route? Would the Ruger Mini-14 magazines in 6.8mm SPC be able to be re-fitted, or the AK re-designed to accommodate this?

 

All food for thought. BTW I think the 6.8mm SPC II ( type II is a different chamber, more improved) is a hell of an improvement over the .223 Rem (5.56mm NATO) and delivers more knockdown punch for the equivalent size and carrying ease of the 5.56 NATO. I could get an AR rifle with the proper barrel, bolt and fittings, which they already make, but I deem the AR to be too prone to mechanical failures over the AK design. Barrett Rifle is now making one with a piston driven system that drives the bolt, and is very difficult to get to be non functional (mud, sand, water, etc). It comes in 6.8mm SPC http://www.barrettrifles.com/home/rifle_rec7.aspx

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I wouldnt bother. The 6.5 Grendel is all over the 6.8spc IMO, not to mention it would be an easier project to do by changing the barrel and setting the headspace on the 7.62x39; you wouldnt even need to change the extractor since its basically the same cartridge.

Edited by RoughRider666
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I see that, RoughRider666. The barrel could be removed and a new barrel put in place and the barrel pin drilled into place after head spacing. How would the magazines work? I know Alexander Arms sells a rifle in 6.5 Grendel and it's even on Bud's Gunshop (and others) with a 10 round magazine. The real catch would be to have a good reliable magazine for the 6.5 Grendel that would lock up in the 7.62 X 39 AK-47 body.

 

Still, for Close Quarter Combat, CQC, The 6.8 SPC would perform quite admirably even against the 6.5 Grendel. I do believe that the Grendel will outperform the 6.8mm Remington SPC in the area of overall accuracy, given the 6.5 Grendel's history of excellent bench rest shooting, and, the penetration test. That 6.5mm round does a good job at penetration. 'However, the Grendel is really pricy for ammuniton, even for reloaders like myself. And, the fact that it is still in an AR configuration. Now, given that it might be a newer piston system, that would make for better reliability, IMO. One other thing, the 30 deg angle on the shoulder does not lend itself to feeding reliability as well as the lesser degree angles of the 7.62 NATO, the 6.8mm SPC, and the 5.56 NATO in regards to their respective shoulder angle.

Edited by AKsarben
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Far as i know a standard AK mag should feed the Grendel just fine; its the same case as the 7.62x39 (220 Russian). Izhmash could make a fortune selling Saiga's in the 6.5 Grendel configuration with very little effort other than a rebarreled X39. I'm not sure about the gas system working or not, but it wouldn't be hard to rework that if needed i wouldn't think.

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How about some entrepreneur individaul building AKs with the 6.5 Grendel barrel and receiver?? I saw a youtube video of how to take an empty 7.62 x 39 shell, and water hydraulic sresize it withing seconds to a 6.5 Grendel. It's on youtube in a search. NOW that would make the brass for the 6.5 Grendel pretty affordable and abundant, as long as you get brass and not steel cases.

 

I would think someone making the AK in a 6.5 Grendel caliber would really rake in the money, providing they sold it modestly for a profit without scalping.

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Here is what Patrick Sweeney wrote about these two chamberings (6.8 SPC and 6.5 Grendel) in the AK platform (you should nab this book!)

 

This excerpt constitutes Fair Use, I hope.

 

On the 6.8 SPC (I will cut out a part intro part where he talks about the builder who undertook a 6.8 SPC AK build, figuring his experience in modifying AR-15s for "wild and crazy calibers" :

 

"What's the big deal?" How about things like a bolt face the right size, making a barrel (*describes barrel problems here*), and then the magazines. *re-iterates point about mags*.

 

He goes on to state the man threw up his hands and gave up. He explains that the advantages of 6.8 (power of 7.62x39 with the accuracy of 5.56x45 / .223 out of an AR-15) do not translate to the AK platform, namely, you don't get the balls-out AR-15 accuracy, and you already had the killing potential of 7.62x39 without all the work.

 

He explains the problem with a 6.5 Grendel conversion has all the problems of the 6.8 SPC "in spades."

 

He says it's a good idea in spirit, chambering the AK in these calibers, but ideally, the benefits just aren't there for home building. He concedes that if either round gains acceptance with NATO forces on a wide scale, expect to see factory AKs in that chambering.

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Yes, the 6.5 Grendel would DEFENITELY find favor herein the U.S. It would be an excellent deer rifle. I think the in-accuracy of the AK-47 stems mostly from the cartridge. From what i've read in my relaoding manual the 7.62 x 39 is not a very accurate round. Some calibers are better than others for accuracy. The 6mm BR is just about tops. The 6.5 Grendel is one of the most accurate cartridges out there. The 6.8 SPC is also a very accurate caliber, along with .308 Winchester.

 

I look at the way the rifle fires. The bolt is LOCKED in position and the firing pin strikes the primer. The bullet travels down the barrel and just after it pases the gas port, not much further, it exits the muzzle of the rifle. The gasses that bleed off the barrel drive the piston backwards, extracting the round and gets the bolt rearward enough to strip another round from the magazine and into the chamber. Like some of th short-piston systems I have read about, it keeps the gassea away from the bolt face and mostly from the chamber area as well. Now, while the bullet is leaving the cartridge and traveling down the barrel, just what is so different from this than from the AR? They say the AK is built too loose, but when the bullet is fired things are locked up tight. Only after the bullet leaves the barrel do things loosen up during recycling.

 

Hence, I don't think that it would be a waste to re-barrel the AK-47 (7.62 x 39) with a Grendel barrel. On youtube.com there is a video on how to make 6.5 Grendel brass by hydro forming 7.62 x 39 brass. The same cartridge is basically used for both rounds, but because of the shape of the brass/cartridge and that fact that it is using a 6.5 mm bullet seems to play a lot into the accuracy of this round.

 

Call it the AK-65 Grendel

 

 

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I wonder how the .308 Saiga, rebarreld to 6.5 Creedmoor would hold up? That would take a simple exchange of barrels and head spacing and then you would use the same magazine for the .308, since it is simply the .308 necked down to 6.5mm. Article here: http://accurateshooter.wordpress.com/2007/11/07/hornady-introduces-new-65-creedmoor-cartridge/

 

DMPS arms makes an AR already in 6.5 Creedmoor from an email I just received from them.

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Yes, the 6.5 Grendel would DEFENITELY find favor herein the U.S. It would be an excellent deer rifle. I think the in-accuracy of the AK-47 stems mostly from the cartridge. From what i've read in my relaoding manual the 7.62 x 39 is not a very accurate round. Some calibers are better than others for accuracy. The 6mm BR is just about tops. The 6.5 Grendel is one of the most accurate cartridges out there. The 6.8 SPC is also a very accurate caliber, along with .308 Winchester.

 

I look at the way the rifle fires. The bolt is LOCKED in position and the firing pin strikes the primer. The bullet travels down the barrel and just after it pases the gas port, not much further, it exits the muzzle of the rifle. The gasses that bleed off the barrel drive the piston backwards, extracting the round and gets the bolt rearward enough to strip another round from the magazine and into the chamber. Like some of th short-piston systems I have read about, it keeps the gassea away from the bolt face and mostly from the chamber area as well. Now, while the bullet is leaving the cartridge and traveling down the barrel, just what is so different from this than from the AR? They say the AK is built too loose, but when the bullet is fired things are locked up tight. Only after the bullet leaves the barrel do things loosen up during recycling.

 

Hence, I don't think that it would be a waste to re-barrel the AK-47 (7.62 x 39) with a Grendel barrel. On youtube.com there is a video on how to make 6.5 Grendel brass by hydro forming 7.62 x 39 brass. The same cartridge is basically used for both rounds, but because of the shape of the brass/cartridge and that fact that it is using a 6.5 mm bullet seems to play a lot into the accuracy of this round.

 

Call it the AK-65 Grendel

 

I think you're right about that, because the 5.45x39 is much more accurate than the 7.62x39. Its the same way the longer more slender bullets like the 6.5(.264) have more resistance to cross winds and superior BC's than a shorter fatter bullets of say something in .308-.312dia.

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Now, can you imagine a .308 winchester necked down to 6.5 mm? All you would have to do is re barrel the .308 Saiga with the 6.5mm Creedmoor barrel/chamber. Yes there is one, and even Hornady makes factory ammunition for this necked down .308 round. The brass being so similar, you could probably use the same magazines of the .308 Saiga. It's slimmer, faster, and has excellent BC, and it's superior to the 6.5 Grendel for velocity. Load it down and you have near the Grendel's top end for speed. Load it normal or up and you really push that 6.5mm round out there!

http://www.hornady.com/story.php?s=763

http://accurateshooter.wordpress.com/2007/11/07/hornady-introduces-new-65-creedmoor-cartridge/

 

 

Would it work?? Hell yes. Even DMPS Panther, an AR style arms maker has this round in it's line up of available chambers.

 

Whadaythink?

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Now, can you imagine a .308 winchester necked down to 6.5 mm? All you would have to do is re barrel the .308 Saiga with the 6.5mm Creedmoor barrel/chamber. Yes there is one, and even Hornady makes factory ammunition for this necked down .308 round. The brass being so similar, you could probably use the same magazines of the .308 Saiga. It's slimmer, faster, and has excellent BC, and it's superior to the 6.5 Grendel for velocity. Load it down and you have near the Grendel's top end for speed. Load it normal or up and you really push that 6.5mm round out there!

http://www.hornady.com/story.php?s=763

http://accurateshooter.wordpress.com/2007/11/07/hornady-introduces-new-65-creedmoor-cartridge/

 

 

Would it work?? Hell yes. Even DMPS Panther, an AR style arms maker has this round in it's line up of available chambers.

 

Whadaythink?

 

This has already been done, its nothing new. Its called the .260 Remington. the 6.5 Creedmoor had a different shoulder degree than the .260 giving it slightly more velocity, but its basically the same idea. 6.5 bullets are 6.5 bullets, the only difference is the case; be it 6.5x55 Swede, 6.5 Grendel, 6.5 Creedmoor, .264 WinMag or .260 Remington. Bottom line, its the same bullet; you just need to use the right case for the AK/Saiga platform, which would more than likely be the Grendel for economical reasons.

Edited by RoughRider666
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The Creedmore is most of what the .260 Remington should have been. .260 handloads with long aerodynamic bullets can be too long to fit in a standard .308 magazines. So they designed the Creedmore with a shorter case than the .260 Rem.

The reduced taper and steeper shoulder angle give the Creedmore a little more powder capacity. But the .260 has the same taper as the .308, so it would take a bit less work to make it feed right in a .308.

.260 ammo is $30 to $50 a box. Hornady sells match 6.5 Creedmore for about $24 a box. Wolf Gold 6.5 Grendel is less than $15 a box. I've had good luck with accuracy with 8mm Wolf Gold.

 

Why not build a .243 from a .308 Saiga? Same case design as .308, ammo is reasonable. Prvi Partizan ammo (Shoots well) for about $16 a box, Win or Fed for less than $20. You can buy ammo for it anywhere. Shoots flat. Load 100 grains for deer, 60 grains for varmints. I don't know of anyone who had a bad shooting .243!

 

Has anyone done this?

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The Creedmore is most of what the .260 Remington should have been. .260 handloads with long aerodynamic bullets can be too long to fit in a standard .308 magazines. So they designed the Creedmore with a shorter case than the .260 Rem.

The reduced taper and steeper shoulder angle give the Creedmore a little more powder capacity. But the .260 has the same taper as the .308, so it would take a bit less work to make it feed right in a .308.

.260 ammo is $30 to $50 a box. Hornady sells match 6.5 Creedmore for about $24 a box. Wolf Gold 6.5 Grendel is less than $15 a box. I've had good luck with accuracy with 8mm Wolf Gold.

 

Why not build a .243 from a .308 Saiga? Same case design as .308, ammo is reasonable. Prvi Partizan ammo (Shoots well) for about $16 a box, Win or Fed for less than $20. You can buy ammo for it anywhere. Shoots flat. Load 100 grains for deer, 60 grains for varmints. I don't know of anyone who had a bad shooting .243!

 

Has anyone done this?

 

Why Bother? you cant really buy .243 in bulk like you can military cartridges like .223/5.56, .308, 7.62x39 and the list goes on...

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RoughRider666, If bulk ammo is the only reason to buy or build a gun, plenty of people sell .243 in bulk. I think what you are looking for is ammo some government decided to sell instead of throw away.

 

Bulk ammo isn't the point anyway. He asked about an easy cartrige conversion. I think I already justified it just fine.

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I'll correct you with the 6.5mm x 55 Swedish Mauser. The base of the shell for a .308, 260 Remington, .243 Winchester, 6.5mm Creedmoor, are all the same 0.473" diameter base. The base would all fit the bolt just fine, no issues. However, the 6.5mm Swedish Mauser is 0.481, which is quite a bit larger base on the shell Overall length of the .308 is roughly around 2.800" give or take, depending on bullets. The 6.5 Swede is an overall length of 3.150" which is also quite a bit longer than the standard .308 Winchester.6.5 Creedmoor probably would be one of the simplest conversions. It's an odd caliber, not military, no big bulk. But, if you hand load anyway it's rather simple..260 Remington would also work, but I think the Creedmoor has a bit of advantage on it for case length.6.5 Grendel would work very well with the AK-47 rifle, 7.62 x 39 as it's base (Grendel) is already that size. It's taking the heavier recoil of the .308 caliber and sizing it down so that you have reduced recoil, but still having size for great energy at the given distance. The BC on the 6.5 bullets is a lot better than that of the .243 Winchester. Bullet just a bit thicker at 0.264 for all the 6.5mm rounds, compared to 0.243 for the 243 Winchester. The idea of effective "thump" on an insurgent was getting away from the 5.56 NATO to something a little more robust (translate thicker) bullet. Hence the 6.5 Grendel, and the 6.8 (actually a .270 bullet) SPC Remington were of considerations as they worked well in the M16 and M4 style AR rifles. They had the flat shooting accuracy of the 5.56 NATO AR's, but with the "thump" of the 7.62 x 39 Soviet.

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I'll correct you with the 6.5mm x 55 Swedish Mauser. The base of the shell for a .308, 260 Remington, .243 Winchester, 6.5mm Creedmoor, are all the same 0.473" diameter base. The base would all fit the bolt just fine, no issues. However, the 6.5mm Swedish Mauser is 0.481, which is quite a bit larger base on the shell Overall length of the .308 is roughly around 2.800" give or take, depending on bullets. The 6.5 Swede is an overall length of 3.150" which is also quite a bit longer than the standard .308 Winchester. 6.5 Creedmoor probably would be one of the simplest conversions. It's an odd caliber, not military, no big bulk. But, if you hand load anyway it's rather simple..260 Remington would also work, but I think the Creedmoor has a bit of advantage on it for case length.6.5 Grendel would work very well with the AK-47 rifle, 7.62 x 39 as it's base (Grendel) is already that size. It's taking the heavier recoil of the .308 caliber and sizing it down so that you have reduced recoil, but still having size for great energy at the given distance. The BC on the 6.5 bullets is a lot better than that of the .243 Winchester. Bullet just a bit thicker at 0.264 for all the 6.5mm rounds, compared to 0.243 for the 243 Winchester. The idea of effective "thump" on an insurgent was getting away from the 5.56 NATO to something a little more robust (translate thicker) bullet. Hence the 6.5 Grendel, and the 6.8 (actually a .270 bullet) SPC Remington were of considerations as they worked well in the M16 and M4 style AR rifles. They had the flat shooting accuracy of the 5.56 NATO AR's, but with the "thump" of the 7.62 x 39 Soviet.

 

+1 on the 6.5x55 swede case info. that saved me the trouble of having to type it myself...lol. HOWEVER, I can't speak for the Saiga .308 as i no experience with one, but i do disagree with your handloading statement on Saiga Rifles. I LOVE my Saiga rifles to death (x39 & 5.45) but i would never handload or waste handloading components on a gun that beats the shit out of brass cases the way they do! These guns were meant to shoot the cheap non-reloadable steel cased European ammo, thus bringing me to my point about BULK ammo in common military calibers!

 

I save my handloading components for all my high quality bolt rifles that wont beat my brass all too hell. With the price of Powder, Bullets and Brass going up, and Primers being almost non exsistant because they're always on backorder; I just dont think that reloading for a Saiga is worth it IMHO.

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My shells after shooting. The .308 shells first:

 

308_after_buffer.jpg

 

And, my .223 rounds after being fired. BTW, they pretty much ALL look like these.

 

223_Rem_8_25_09.jpg

 

I fixed both my Saiga .223 and the Saiga .308 for less than a hand full of bullets. Used a car door trim molding I got at Autozone.

 

The Saiga does seem to respond to good hanloads.

 

308_targets_sept15.jpg

 

3shot_group_close.jpg

 

saiga_223_target-7-18-09.jpg

This is a 0.580" group with BLC-2 powder.

 

And another one from the .308....

308_target_710_MOA.jpg

 

 

So, I for one, think that the Saiga deserves to be shot with good ammo and it's worth the time to work up a hand load for it as well.

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My shells after shooting. The .308 shells first:

 

308_after_buffer.jpg

 

And, my .223 rounds after being fired. BTW, they pretty much ALL look like these.

 

223_Rem_8_25_09.jpg

 

I fixed both my Saiga .223 and the Saiga .308 for less than a hand full of bullets. Used a car door trim molding I got at Autozone.

 

The Saiga does seem to respond to good hanloads.

 

308_targets_sept15.jpg

 

3shot_group_close.jpg

 

saiga_223_target-7-18-09.jpg

This is a 0.580" group with BLC-2 powder.

 

And another one from the .308....

308_target_710_MOA.jpg

 

 

So, I for one, think that the Saiga deserves to be shot with good ammo and it's worth the time to work up a hand load for it as well.

 

Im curious to know what you did to your rifle to get them to stop banging brass. My buddy has a Saiga .223 and that thing beats brass so bad it's almost always unusable even after the resizing die. it literally caves the side and or shoulder in about 90% of the time...its horrible! thats why he wont put anything but steel cased ammo through it anymore.

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I also put a short piece of coil spring in the chanel where the rebound spring goes. I think it helps lessen the severity of the recoil on the bolt, hence less ejection force on the actuall spent brass. If you want, I can post a picture of that. Plus, I use that small bit of door guard on the dust cover where the shells more often than not hit.

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I also put a short piece of coil spring in the chanel where the rebound spring goes. I think it helps lessen the severity of the recoil on the bolt, hence less ejection force on the actuall spent brass. If you want, I can post a picture of that. Plus, I use that small bit of door guard on the dust cover where the shells more often than not hit.

 

yeah id like to see some pictures of what you've done.

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Ok. For the coil spring is the following picture. I have since changed it a bit to simpy put the cut coil spring on the tip of the recoil spring before inserting it in the tube. I've not had any issues with it and it seems to provide just a bit more stiffness to lessen the bolt coming back. It's the same green spring, but now not "in" the holder, but resting on the tip:

 

rebound_spring.jpg

 

The buffer for the dust cover is circled in this picture. I did a crop and you can see the small piece encircled. Since I repainted the dust cover it got painted as well. *smiling*

 

shell_buffer.jpg

 

You can see it now in the larger picture of the overall rifle.

 

Saiga_223-brown.jpg

 

Hope the pictures help.

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