AR-15 in AK calibers

[Crowbait]

I've purchased a Bear Creek Arsenal complete upper in 7.62x39. It's a side charge complete with bolt & firing pin. I've pinned it to my DPMS 5.56 lower assembly and it functions beautifully with no other modifications. The only previous mod I did to the lower was install a Velocity 4.5 lb trigger assembly.

 

[Deerhurst]

So much mis information!

7.62x39 is fine in an AR. If you have really hard primers use an enhanced firing pin and a little stronger hammer spring. I shoot mostly Tula with a standard firing pin and a POF 4.5lb trigger. It sets off 100% of primers. You can roll your own 7.62x39 too for whatever. Get a .308 barrel chbered in x39 and load with 308 projectiles. Run the .311s if ya gotta.

AKs are not harder to suppress. They just suffer from a larger chance of thread concentricity issues. I used to 3gun with a suppressed AK. Now I rock a suppressed Suchka. With the right ammo it's like any other semi auto, just bolt noise.

5.45 is not really all that fragile with Hornady producing brass and projectiles. Yes, it's more expensive to buy the brass than 223 but it's also a little less common. It makes fantastic varmet loads.

I also run a 5.45x39 AR. The primers in the RAS ammo, Barnul?, are crazy hard. 4.5lb POF and an enhanced firing pin and it's 80% or so most days. Runs great suppressed too. not sure a heavier hammer spring would help. The primer is already mangled and always goes off on the second hit. I think the firing pin protrusion is still not quite enough. My 5.45 hand loads are never an issue.

With 5.45 the only difference in the mags from 5.56 is the follower. For the most part 5.45 and 5.56 tend to feed ok from each other's mags. Lots of info on modding PMags for 5.45 too.

Personally, I'm wanting to build an AR in 9x39.

 

[Boboclown]

With 5.45 the only difference in the mags from 5.56 is the follower. For the most part 5.45 and 5.56 tend to feed ok from each other's mags. Lots of info on modding PMags for 5.45 too.

And curvature, its just way more forgiving with 5.45 than it is with 7.62x39.

 

[Deerhurst]

And curvature, its just way more forgiving with 5.45 than it is with 7.62x39.

View attachment 806128

As long as you can keep the nose up it feeds.


What mag is that? Looks Bulgarian but not a 5.56 mag I recognize. Is it AK74 or 47 width?

 

[AK0perator47]

It's a 556 from what I see on top of a Bakelite

 

[Boboclown]

As long as you can keep the nose up it feeds.


What mag is that? Looks Bulgarian but not a 5.56 mag I recognize. Is it AK74 or 47 width?

The one on top is a black beryl mag (5.56), the bottom one is an AK74 bakelite.

 

[223to45]

So much mis information!





I also run a 5.45x39 AR. The primers in the RAS ammo, Barnul?, are crazy hard. 4.5lb POF and an enhanced firing pin and it's 80% or so most days. Runs great suppressed too. not sure a heavier hammer spring would help. The primer is already mangled and always goes off on the second hit. I think the firing pin protrusion is still not quite enough. My 5.45 hand loads are never an issue.

I run a 5.45 AR , been totally flawless.
I run a Velocity 4lb Steel trigger and ASC mags

 

[wired]

I ran a metric crapload of 7.62x39 through my old ( Wish I still had it ) Colt 7.62X39 AR. Thousand and thousand of rounds. I could handily hit golf balls at 100 yards with it which would send them into orbit. Never an issue with it. Great gun.

 

[Deerhurst]

I run a 5.45 AR , been totally flawless.
I run a Velocity 4lb Steel trigger and ASC mags

What ammo do you run? My RAS ammo seems to have stupid hard primers. They are hit hard enough its a small crater but doesnt always go bang.

 

[Deerhurst]

The one on top is a black beryl mag (5.56), the bottom one is an AK74 bakelite.

Ah! I havnt gotten my hands on any beryl mags. I run Circle 10 in my 223 Saiga and mostly bulgy polys in my 74. Sometimes Russian or East German bakes.

 

[fstdraw]

Question: Why has 6.8 fallen out of favor?

 

[AK0perator47]

Question: Why has 6.8 fallen out of favor?

A lot of people still have a 6.8 but the 6.5 outperforms it.

 

[AK0perator47]

 

[billdeserthills]

I've purchased a Bear Creek Arsenal complete upper in 7.62x39. It's a side charge complete with bolt & firing pin. I've pinned it to my DPMS 5.56 lower assembly and it functions beautifully with no other modifications. The only previous mod I did to the lower was install a Velocity 4.5 lb trigger assembly.

I read somewhere that it's hard to find a good working AR magazine that will feed 7.62x39, what mags are you using?

 

[Deerhurst]

I read somewhere that it's hard to find a good working AR magazine that will feed 7.62x39, what mags are you using?

You have 2 real choices for dedicated mags. Cproducts or ASC. Some swear by CProducts. I use ASC.

 

[billdeserthills]

Thanks, maybe I'll try one

 

[Crowbait]

I read somewhere that it's hard to find a good working AR magazine that will feed 7.62x39, what mags are you using?

I've heard ASC are good. I'm using Duramag. I've had no issues.

 

[Boboclown]

Another option is a lower that takes AK mags like the KS47, only problem with that route is you either have to buy a new bolt carrier or modify the one you have.

 

[223to45]

What ammo do you run? My RAS ammo seems to have stupid hard primers. They are hit hard enough its a small crater but doesnt always go bang.

Mostly Silver Bear ammo

 

[arakboss]

I've built several Ar uppers in 7.62x 39. The combo of the specific barrel and mags I use make them very reliable and quite accurate compared to most ak's. For a 16" build, carbine gas works great and a h2 buffer is about right with the size of the gas port in the barrels I use. I have around 5000 rds through one and 1 broken extractor is all that I have had fail. I use a kak bolt with an enhanced firing pin. The lower I use has an alg trigger with standard springs and it ignites all ammo without fail. Cleaning it every 750 rds or so keeps it humming right along and I run a lot of wolf steel through it. With wolf military classic 123 hp ammo it shoots honest 1-1/8" 5 shot groups. This Ar goes to the range with me almost every trip.

What barrel do you have or have you used. Did the barrels have oversized feed ramps in the extension?