Do it yourself SBR

[mgconnor13 206]

So I would like to build a 7.62x39 SBR AK. I want to do it by myself as much as possible. I have fairly limited tools so I want keeps this project as simple as possible. If I can avoid welding and machining as much possible that would be all the better. Having a SBR is more important to me then having a true semi-auto "krink" copy, I plan to use this rifle as a trunk gun/range toy when it's done.

 

Way I see it I have three options as starting points for this DIY "krink" project (any other ideas are welcome).

1) Buy a 7.62 Saiga, convert it, and chop it.

2) Buy a Arsenal SLR-107U (or equivalent "krink" style rifle with a full length barrel) and chop it and re-thread it.

3) Buy a AK pistol, add a rear trunnion block and a stock.

 

Option one seems like the most work, conversion and then shortening the gas system and shortening the barrel.

Option two while pricey (around $1000 for the gun) would be the closest thing to a "krink" when done and all I would have to do is shorten the barrel and thread it

Option three seem to be some thing I can do at my skill level with out spending a ton of money.

 

Before I even attempt this DIY AK SBR project I have a few questions.

 

1) Any other legal issues beyond the normal State and Federal rules involved in building my own NFA? 922r doesn't apply to NFA items?

2) Are there any AK pistols/rifle out there that would be a good candidate?

3) Do "krinks" have any quirks or unique issues compared to their full size big brothers?

4) What kind of performance can I expect out of a 12" barrel? how about a 8.3" barrel? (8.3" is what the ak-74u was right?)

5) Is there an optimal barrel length?

6) Any issues with bullet weight/ twist rate with short barrels? Any recommendations for ammo?

7) Muzzle booster necessary/helpful? If so what are my options and what's the pros/cons of each booster?

8) Do "krinks" have increased fouling or reliability issues other then the usual issues caused by the higher preasure (caused by the gas port being closer to the chamber) and shorter gas impulse?

9) Are AK pistols even a viable option for this project? How well do AK pistol function? (This project could be my trunk gun)

10) Any thing I haven't thought of? (yes I know that's really broad)

 

This project is still in the early planning phase so I'm not committed to anything yet, I'm exploring my options for now. Any thoughts, experiences, tips, or ideas would be great. The local CLEO is friendly so I'm going to be doing this in my name instead of a trust. Reason I'm going with 7.62x39mm is because I already have a 7.62 AK and I want to use a round that will have good performance in a SBR.

Edited March 23, 2010 by Rusty truck

[KrisFox 69]

Draco pistol.

 

Submit tax stamp and enjoy your pistol as you wait.

 

Once Stamp comes back drill the rear plate and attach a folding mech or fixed stock such as an ACE.

 

Presto, SBR AK for under $700 and less than 30 min labor.

 

Edited March 23, 2010 by KrisFox

[Cobra 76 two 2,677]

This is a long range plan of mine as well....after I get a new septic system put in and tied into my existing drainfield. That's gonna suck all of the out of me for awhile.....ugh.

 

[sunnybean 939]

That's a lot of questions.

 

Basically, what KrisFox said. The easiest and most inexpensive way is to buy a Draco, F1 it, and put a folder on it.

[nalioth 405]

A very long and detailed thread on this came up over at The High Road forum a couple months back . .

 

Then again, you could always search this forum for all the previous posts on this subject. .

[elvis christ 451]

I plan on drilling and tapping the rear trunnion of the AK pistol I built last year, to accept an ACE folding mechanism and stock. This is all based on Alabama repealing their ban on SBR/SBS, which looks like it probably won't happen, but I'm cautiously optimistic.

[mgconnor13 206]

Well from what I've read the pistol to SBR seems the best route to go for me. Thanks, soory for the multiply posts.

 

The Dracos have threaded barrels right? I'm thinking of going with a Bulgarian Krinkov 4-Piece Flash hider. Any one have any experience with the Bulgarian hiders? The Noveske KX3 is based of the bulgarian hider if i remember right? I have a KX3 on an AR and it does a good job of hiding flash and directing the blast. I noticed it produces a slinky like sound as the muzzle blast repeatedly bounces of the front and back walls at the local in door range, it sound really weird if your not expecting it. Will the Bulgarian hider throw sound in a similar way?

Edited March 23, 2010 by Rusty truck

[KrisFox 69]

[mgconnor13 206]

I knew you would say that. I have thought about the PWS a bit. A krink style break is on the top of my list followed by the PWS.

[BobAsh 582]

Yeah, Tony just did this with a SIG 556 pistol. The SBR came out awesome and no real work involved, just bolt-on stuff.

[mgconnor13 206]

thanks bob. I figured a bolt on stock takes a lot of work out of building. Bet that sig 556 is really nice.

[chevymann 13]

I've got a couple of Draco's that I oneday will SBR... Trying to resist the temptation of the Sig pistol, but it's not working...

[BobAsh 582]

thanks bob. I figured a bolt on stock takes a lot of work out of building. Bet that sig 556 is really nice.

 

It's badass. Of course, the big job on an SBR is the gas system and you bypass that whole project with the pistol.

[mgconnor13 206]

Re-doing a gas system is above my skill level and current tooling. Figured a pistol conversion would be the easiest way to build a AK SBR. I'm really excited that the sheriff where I live signs forms 1s so now I'm have all sorts of ideas for things I want to build. Any one have recommendations on what AK pistol to use? All I've found so far is the Dracos. Are there any other pistols out there? I'm looking to build a SBR I can through in my truck and forget about, that and to go scare small children at the range.

[BobAsh 582]

i'm looking to build a SBR I can through in my truck and forget about...

 

I know you're kidding, but remember an NFA weapon must remain in your control at all times.

 

It's a great project. I don't really have any suggestions for a pistol though.

[nalioth 405]

Re-doing a gas system is above my skill level and current tooling. Figured a pistol conversion would be the easiest way to build a AK SBR. I'm really excited that the sheriff where I live signs forms 1s so now I'm have all sorts of ideas for things I want to build. Any one have recommendations on what AK pistol to use? All I've found so far is the Dracos. Are there any other pistols out there? I'm looking to build a SBR I can through in my truck and forget about, that and to go scare small children at the range.

I would suggest the Draco/Champion pistols. They are basically unfinished (no fun switch or butt stock) Romanian submachine guns.

 

Any other "AK pistol" is going to be made from a cut up parts kit, and if the builder didn't do a good job with it, the gas system can be problematic (not to mention other potential issues).

[mgconnor13 206]

Yeah I know I have to be in procession of it. I meant it as a "I can grab it as I head out the door and go gun", and not have to worry about if it will work even if it's been riding around behind the seat of my truck for six month with out cleaning and a whole lot of shooting. I'm pretty up tight about weapons maintenance but I still want a gun I can through in the mud with out any issues.

 

How do NFA items work with spouses? If I remember right the ATF doesn't make any exceptions for spouses, so i would have to be there if my wife is using a NFA item in my name.

 

Is the barrel nut on a Draco welded and how easy is it to remove? I want to use a Bulgarian krink flash hider for the krink look

Edited March 24, 2010 by Rusty truck

[nalioth 405]

How do NFA items work with spouses? If I remember right the AK doesn't make any exceptions for spouses, so i would have to be there if my wife is using a NFA item in my name.

If you want your spouse to be able to have the keys to safe, you'll go the trust route and name them on it as an officer of the trust. Same $200 per gun / more freedom (as in the people you want to be able to have possession of it). If your house burns down, and your wife rescues your SBR that the sheriff signed off on, y'all gonna be in a lot of trouble. In the same situation, if there's a trust and she's a named officer, no problem at all.

 

 

Is the barrel nut on a Draco welded and how easy is it to remove? I want to use a Bulgarian krink flash hider for the krink look

It's a teensy weld. A dremel'll knock it off in short order.

[mgconnor13 206]

good to know i could dremel off the nut. I'm not worried about the whole possession issue since all my guns sit in a fire/water proof safe and are insured. My wife doesn't touch the guns except for when she asks me to take her to the range.

[BobAsh 582]

Yeah I know I have to be in procession of it.

 

 

I wasn't trying to school you buddy, a lot of my posts are intended for the larger audience.

[mgconnor13 206]

Sorry if it sounded like I was coping an attitude. I appreciate you sharing your knowledge. I'm doped up on pain killers right now from getting my wisdom teeth pulled yesterday so please excuse any typos, incoherent statements, or just plain random/retarded stuff I might say for the next few days. Again sorry about that bob.

[BobAsh 582]

We're cool my friend.

[mgconnor13 206]

Any one have any data on muzzle velocity and kinetic energy on short barrel AKs? I'm curious how much energy you loose by cutting down the barrel. Any recommendations for defensive 7.62x39mm ammo to use in a SBR?

[Moe Zambeak 53]

The 7.62x39 is a perfect round for an SBR. Here is a snippet from a recent article I read involving the strengths and weaknesses of the 7.62x39 round:

 

Here are potential untapped strengths of the 7.62x39. First, because of the relatively small powder volume versus bore size, relatively little performance is lost as barrel length is reduced. This makes the 7.62x39 a perfect candidate for very short carbines. For example, a load that replicates M43 using Accurate #1680 powder will lose only about 70 fps when barrel length is reduced from 16 inches to 14 inches. Going down to a 12-inch barrel only loses another 83 fps, while a 10.5 inch barrel will still fire the 123-grain bullet at just over 2100 fps. The 7.62x39 is an ideal cartridge for a short-barreled rifle, provided a bullet that produces good terminal ballistics is used.

 

Link for the rest.

[mgconnor13 206]

Thanks. Short article but a good read. I didnn't realize how little 7.62 is effected by barrel length. While I wasn't planning on doing anything crazy with an SBR AK that section of the article at the end on heavy weight bullets and suppressors got me thinking. More plans for the drawing board I guess Any one have ammo recommendations for defensive ammo? I picked up some of Hornady's steal cased V-max the other day but haven't tested that yet. Shot a ton of wolf HP and it ran just fine for me. I know there's not a huge market for 7.62x39mm ammo just because of all the cheap mil surplus out there but I'd like to find so high end hollow points to keep around.

[mgconnor13 206]

Any one know where I could get a new or used 100 series style side folder to use? I've seen a few krinks done like that that came out well. Also been hunting around for a rail system. The draco hand gaurds are standard length right? Any verdicts on a stand alone gas rail and a hand guard verus a full quad rail? I'm looking for suggestions for a flash hider/ brake too while I'm hunting around for a pistol to start the build.

Edited March 27, 2010 by Rusty truck

[mgconnor13 206]

Would putting a quad rail on a AK pistol be "intent" to build an AOW? I just picked up an aimpoint micro and I want to mount it to a Draco while I wait for the Form 1 to process.

[getitat 609]

Hello

I'm thinking "no". Many pistols are sold that way, such as the Red Jacket pistol I have.

 

guido

[BobAsh 582]

No, lots of "real" pistols have a rail under the barrel for a light.

[Steppe Sweeper 22]

PWS CQB-30 the neo-krink brake.

Plan on one for my S-308 16", but haven't even started conversion yet. Getting her snoot to 5/8x24 is an even bigger pandora's box