Building my own 7.62x39 AR

[breid1970 327]

Ok, so Dubs and were brainstorming and we decided that my next project is going to be a 7.62x39 AR style rifle. I know that sig makes one for about 1400 plus. I figure I can buy the lower complete for less then four and the upper for about the same. My question is who and where makes the magazines? And will Russian standard ammo work well with it. Thanks guys.

[drkstrw 15]

From what i understood it uses regular AK-47 magazines.

[mostholycerebus 415]

I only know a little about this because what I found did not leave me wanting to go through with the project. The AR platform was designed ground-up to take a straight magazine. Even 5.56 30 round mags have had problems because of the gentle curve, it was designed to take straight 20-round mags. The system was designed for relatively clean, brass 5.56. Dirty, steel x39 with hard primers cause their own issues, even if you can get them to feed. Speaking of ammo, very good 5.56 is available in plenty (during non-panic periods) as is match-type ammo that can take advantage of a well-built sub-moa rifle.

 

Ive been watching prices, and right now its cheaper to buy a decent complete rifle than build one. Prices are slowly crashing, but many of the parts vendors havent figured that out yet, while the big retail places rifles prices are dropping like a rock.

 

Personally, because I love the x39 ballistics, im building a 300BLK AR15. It uses 5.56 cases and .308 bullets, so reloading is relatively cheap. It uses cheap 5.56 mags, and the only difference between a 5.56 rifle and a .300 rifle are the barrel, so parts are readily available and decently priced. Like the x39, its a great round for SBR applications, and the modularity of the AR15 platform appeals to me on a SBR. There are many, many modern .308 bullet designs available, and at long range the .300blk bets x39 ballistics.

 

I feel x39 has a place, but we wont see it for years. It has a few advantages over 300blk, but cheap russian imports have stymied development of a 'modern' x39 round.

 

But hey, anything is possible with enough money, so if its what you really want, go for it.

[Sdustin 578]

I second .300 blackout. Especially if you reload. You can use any ar15 556 mag that you can get anywhere. I wouldnt do it unless I had tens of thousands of roounds stock piled and also liked practicing stoppage drills.

[getitat 609]

Hello

 

The "ASC" mag's are the acknowledged primo feeding device. Ditto the Bushmaster mag's (no, really!) but I suspect they are actually ASC mags and followers w/ a Bushmaster floorplate.

I went with the 7.62x39 because in doing so I would be reloading cartridges for my AK based firearms as well as my AR-39. I try to limit new caliber introductions into the reloading library.

I have a bunch of mil-surp ammo, but enough is never enough....

 

JMHO..

 

-guido in Houston

"God Loves Liberty"

[mostholycerebus 415]

I went with the 7.62x39 because in doing so I would be reloading cartridges for my AK based firearms as well as my AR-39. I try to limit new caliber introductions into the reloading library.

See, my plan is to get a saiga in 5.56 and get the TAKD BASTARD mod for it. Then I will have cheap, durable, lightweight mags that will work in a 5.56AK, AR, or .300blk AR. 5.56 and .308 bullets, and 5.56AR parts will always be available in the US. The only unique piece will be the .300BLK barrel. Which, BTW, TAKD is running AK barrels for too.

[U.S. Pratorean 1,234]

They are great guns and work well. Iprefer this caliber over 5.56. I have 2. One is a Colt the other is a Bushmaster. The mags I use are the C-products mags which I think are now ASC and National mags. The National mags were notorious for malfunctioning but I changed the crap mag followers they came with, with Magpul no tilt green followers and stretched the spring a tad and I have had no problems with them. They look like 5.56 30 round mags but are really 20 rounders. I also had them all duracoated.

[Sdustin 578]

I think colt stopped making 7.62x39 ARs since there's so many problems. In just saying for me to chose that over blackout there would have to be something to out weigh all the issues I'd have to overcome. like thousands of rounds I already had, keeping number of rounds to have on hand makes sense, but any rifle I've got number one is reliability. I've got two ARs and one saiga right now. I was to pissed when my s308 wouldn't feed with my High cap mags. I got it fixed now and trust it to work no matter what. And I would "go to war" with Any of by rifles.

 

One of my ARs is a pistol with a 9" barrel and it's a 300 blackout. I couldn't be happier with it. It has jammed but it was a handloaded round lightweight bullet that's much too short I only use it to hunt with. With my regular load of a 150 grain Amax it's been 100%. Ive also worked that load to hit at the sane POI as my 125 grain hunting load and rem UMC 115 grain at 50 yards.

[U.S. Pratorean 1,234]

I think colt stopped making 7.62x39 ARs since there's so many problems.

It was really because it came out right before the AWB and never had a chance to be marketed and Colt discontinued production. Unfortunate because it is an excellent piece. Mine as well as the BM are 100%. Until the 300 round is available in similar to x39 quantities and price I'll stick with the x39. However, if the aforesaid does come to fruition, a barrel change and I'm GTG.

[Sdustin 578]

Before sandyhook I was getting UMC for 120 bucks for 200 rounds. And that ammo is amazing. One hole groups and crimped bullets sealed bullet and primer it's boudle struck cases same as lake city brass. It's good ammo very good ammo. And at 12 dollars a box it's a good price. If shit ever gets back to normal I'll be stock piling a couple thousand of rounds.

 

Now if you reload then you can load it all day, cut down 556 brass and use any .309 bullet.

[ShadowFire 220]

Ok, so Dubs and were brainstorming and we decided that my next project is going to be a 7.62x39 AR style rifle. I know that sig makes one for about 1400 plus. I figure I can buy the lower complete for less then four and the upper for about the same. My question is who and where makes the magazines? And will Russian standard ammo work well with it. Thanks guys.

 

ASC makes the mags for the standard AR lower.

 

If you're paying 1400 you're getting raped. I built the lower, ordered the upper on this one. Total cost about a grand. Gas Piston 7.62x39 AR

 

 

Built by Black Rifle Arms.

 

As for your upper, it depends on who builds it if it will run the surplus/imported ammo. I can run imported ammo (steel cased) in mine all day long. It also depends on a particular part you either use or do not use in building your lower.

 

That part is, a wolff extra power hammer spring. Lights the primer up, every time.

 

Black Rifle Arms tests their uppers with wolf ammo. I'm glad I bought mine from them, they do good work. They also build DI uppers too, but 7.62x39 DIs are dirty shooters. Reason is the imported ammo out there shoots dirty, nature of the beast, it is what it is. Gas piston is easier to clean, it dumps a lot of the gas into the outside air near the gas block because it's a short stroke system without a gas tube.

 

We might want to move this to the Other Rifles section since this is not about an AK style rifle.

[czmadness 1]

Sota Arms for the barrel and bolt and Model 1 for the enhanced firing pin. Cheap and works well...

[ShadowFire 220]

I forgot about the firing pin adjustment, good call cz. Yeah the firing pins make a big difference. I'm not sure who makes the pin for mine but Black Rifle Arms installed it on my upper. Every little bit helps. I have no idea who makes the barrel on mine either but it's an M4 profile barrel, melonited 1/10 twist rate and has five lands and grooves.

[breid1970 327]

After all the waffeling i have decided to go and begin work on a 6.8. i will be getting a lee single stage reloader in june. all is well.

[ShadowFire 220]

I think you'll like the 6.8. A friend of mine has a mid-length one that he likes to hunt with. He likes his, I got to fire it, good punch has some authority to it when you send a round down range.

[getitat 609]

Hello

 

LMT has purpose-built (not 5.56 modified) "enhanced" 7.62x39 bolts built for an unfulfilled military contract that are bulletproof.

That is the only Achilles heel with other AR-39 uppers.

Those and ASC mag's are the keys to reliable weapons.

 

JMHO....

 

-guido in Houston

"God Loves Liberty"

[Sdustin 578]

What chamber in 6.8 there's like three I think.

 

If your going to be reloading I'd get the non sammi spec since you can get LOTS more speed from it and handloads.

[Nailbomb 10,221]

the 7.62x39 ARs that use rock and lock mags I've heard good things about. it solves a lot of the basic issues of the cartridge going into a weapon system not designed for it.

 

expensive though. as much as I would love one, I'll stick to feeding it in the guns it was made for.

[ShadowFire 220]

6.8 Chamber variants. Take your pick.

 

(2004)Remington 6.8x43 SPC-(SAAMI)- has a .050 freebore and when submitted to SAAMI had the correct 45 degree cone angle, has a .278 diameter freebore. Some drawings from PTG has a 80 degree cone angle, no one knows where the error originated.

(Jan 2006)6.8 Remington SPCII-(SPCII)- had a .100 freebore originally drawn by Art of SSA or Barrett not known for sure had the correct 45 degree cone angle, has a .278 diameter freebore, .3085 neck. Some drawings from PTG has a 80 degree cone angle.

(2007)6.8x43 DMR (DMR)- has a .095 freebore, .277 dia and a .305 neck diameter it was designed to correct the bad 80 degree cone angle and be a little more accurate in stainless match barrels because of the shorter freebore and .277 dia leade. Only used in ARP stainless match barrels.

(2008) DMR-C enlarged only enough to take into account the thickness of the chrome in the chamber, neck .0307/.3075-Used only in the chrome lined barrels we had produce in late 2008 and sold in early 2009

(2009) 6.8x43- has a .095 freebore, .2775 dia with the correct 45 degree cone angle and a .3085/.309 neck. A call came in one day which I missed so they called Tim_W, they said they were planning to submit a new drawing to SAAMI with the help of either Rem or Hornady to get the better spec chamber approved by SAAMI. They said they were planning on submitting the SPCII but wanted our input since we had tested the chambers more than anyone. Tim and I talked about what would be best for a true combat chamber, not a hunting or match chamber.
We added a very small amount of taper in the neck and body to aid extraction, the freebore was increased to .2775 from what the DMR chamber had, The neck dia was increased to .3085/.309 taper. We guessed if the mil would adopt the cartridge they would call it the 6.8x43 Nato so we just dropped the "Remington" and "SPC" from the name and Tim sent it back to the person that called noting these would be our recommended changes. Of course nothing happened with SAAMI but that is how the 6.8x43 that I presently use came about.

Noveske mod 1-no real idea, they say it has a .100 freebore.

(2010) New SPCII- Ben with Bison posted a new SPCII drawing that shows a .114 long freebore with .278 diameter and the correct 45 degree cone angle, everything else is the same as the other SPCII.

IMO all of these chambers except the original "Remington 6.8x43 SPC"(SAAMI) will handle high performance ammo.

These chambers seem to confuse many possibly because the public has been exposed to the chambers and given more info than what has been released about the 5.56 and 308 chambers. There are 14 308 chambers that I know about but most of the public thinks there are only 2 the 308 and the 7.62x51 nato. There are at least 10 223/.556 chambers that I know of, the 6.8 isn't different it is just that there is a lot more info being passed around to the public about it.

 

 

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