Builiding Registered SBR from an AK "pistol"

[Dr. Tad Hussein Winslow]

If one were so inclined to register and build an SBR with BATFE on one of these AK 'pistols' on the market:

1. Do the existing AK components such as stocks/p-grips fit right onto the receiver as they would on any other AK?,

OR

2. No, they are like the Auto Ordance Thompson 'pistols', where they specifically make the rear of the receivers so that you cannot attach anything, SBR license or not,

OR

3. Depends on the AK pistol in question - if so, which are yes and which are no?

OR

4. Some other possibility I hadn't thought of?

Thanks.

 

[Sam1911]

Generally, the rear trunion on pistol builds is a new-production piece designed to be a flat plate, or sometimes a flat plate with a sling attachment point.

They are careful to make the trunion not accept any kind of AK stock easily.

You'll need to remove the rear trunion and install either a standard AKM one or an AKS-74 style, or whatever will accept the stock you want to use.

Otherwise, yes, just about any other part should work.

-Sam

 

[nalioth]

I will use the Romanian made Draco / Champion pistols as an example:

1. Do the existing AK components such as stocks/p-grips fit right onto the receiver as they would on any other AK?,

These pistols are closer to "a real AK" than any other AK currently imported. Their receivers are milspec (just not fully finished [i.e. the fun switch is missing]) right off the military production line.

All AK parts and accessories will fit (taking barrel length into consideration).

2. No, they are like the Auto Ordance Thompson 'pistols', where they specifically make the rear of the receivers so that you cannot attach anything, SBR license or not,

Once you receive your approved form 1, you'd basically remove the rear rivets, weld up the rivet holes and install whatever rear block arrangement you desired (standard fixed stock AK rear tang, side folder rear block, or underfolder rear block).

The Draco / Champion pistols are the only ones I'd consider SBR'g, as the ones made from cut up Romy G kits have "guessworked gas systems" and also have had their chrome lining advantage removed (cutting the barrel slices through the chrome and this can lead to the chrome flaking away).

The Romanian pistols have been manufactured (in submachinegun form) for over a decade in Romania, and should provide a quality SBR here.

 

[smince]

A thread on making a Draco SBR:
http://www.warriortalk.com/showthread.php?t=61984&highlight=draco

 

[nalioth]

A thread on making a Draco SBR:
http://www.warriortalk.com/showthread.php?t=61984&highlight=draco

Forum signup required to see that link.

Nice way to build up the numbers over there


I did not advise the method used in that thread ( drilling and tapping the existing rear block ) because (to me) the rear block appears too thin to hold up to much use when a stock is attached like that. The rear block used is a virgin under folder block, and is not designed to have a stock attached to it at it's backside.

FWIW: The Romanians employ a standard fix stock tang in their shorties:


. . and there are some fine examples of SBRs from here in the USA:
(not my pix - please note these have had standard stock tangs installed as I outlined in my earlier post)
A Champion pistol-turned-SBR


A Draco pistol-turned-SBR


I highly suspect that installing a fixed stock tang and cutting it for an Ace internal stock block (or not cutting it, and using an Ace external block) would make be more durable than drilling and tapping the existing factory rear block.

 

[Shadow Man]

A SBR AK-type with a folding stock would make a nice PDW-style weapon wouldn't it? Hmm...I'm sure I have $200 laying around here somewhere...

 

[Ian]

I'm working on building an SBR AK myself, and using a cut-down Romy kit to do it. I looked into using a Draco pistol, but those all have 12" barrels. I didn't want to go through all the work of making an SBR to only have a 4" reduction in barrel length. My cut down kit has a 9.5" barrel, which is much more in line with what I wanted (a very compact rifle for toting around in the boonies).

 

[THE DARK KNIGHT]

I know nothing about SBR and I live in NJ thus the only SBR I will ever get to play with here is on the X-Box. Heck I can't even own the Draco pistol here. But IMO why play with a cut up kit when you can just get a already made rifle for 2.5" more barrel.

Also out of curiosity, would it be possible for someone with an SBR stamp to drill two big holes in the back and put an underfolder on there?

 

[Sam1911]

would it be possible for someone with an SBR stamp to drill two big holes in the back and put an underfolder on there?

Nalioth answered already:

Once you receive your approved form 1, you'd basically remove the rear rivets, weld up the rivet holes and install whatever rear block arrangement you desired (standard fixed stock AK rear tang, side folder rear block, or underfolder rear block).

-Sam

 

[nalioth]

Also out of curiosity, would it be possible for someone with an SBR stamp to drill two big holes in the back and put an underfolder on there?

Why wouldn't it be possible?

The only regulated part of an SBR is the barrel length. It can have any stock on it (or no stock at all).

The Draco and Champion pistols come with virgin under folder rear blocks, so installing an underfolder would be easy enough (provided you have all the hardware).

 

[THE DARK KNIGHT]

Yeah, I see he posted that, but what I meant was, could an underfolder be installed without changing the block? It looks to me from pics like the underfolder just is a big rod that goes through the receiver walls and attaches to that.

 

[THE DARK KNIGHT]

Why wouldn't it be possible?

The only regulated part of an SBR is the barrel length. It can have any stock on it (or no stock at all).

The Draco and Champion pistols come with virgin under folder rear blocks, so installing an underfolder would be easy enough (provided you have all the hardware).

OK, thank you. Yeah I was wondering about it being mechanically possible, I know it is legally possible.

 

[Sam1911]

Rear trunion doesn't look like an AKM trunion, but doesn't look to me like a pistol rear. But I'm not sure.

Look at this:

The trunion does support the underfolder mechanism, so I can't imagine the bare receiver shell doing an adequate job.

-Sam

 

[Sam1911]

The Draco and Champion pistols come with virgin under folder rear blocks

Ahhh, so they just don't drill/punch the holes through the receiver shell for the underfolder parts? Cool. Makes sense -- why invent a blank-off type rear trunion from scratch if there's a common surplus part that will do the job without alarming the ATF?

-Sam

 

[THE DARK KNIGHT]

Yeah see, I had a feeling that was the case from looking at pictures. Draco SBR underfolder is my dream gun lol.

 

[Sam1911]

Yup, pretty cool. Though I have to say I'm QUITE fond of the AKS-74U that my build-buddy did off a complete, perfect (apparently unfired) kit. Just gorgeous!

And, yes, he has a 45-rd RPK mag for it so it can be "taller" than it is long! LOL!

-Sam

 

[nalioth]

The Draco and Champion pistols come with virgin under folder rear blocks

Ahhh, so they just don't drill/punch the holes through the receiver shell for the underfolder parts?

They don't drill the rear block, either. Which means that it will be able to be used with any countries under folder types (the different countries have different arrangements of their mechanisms).

 

[Sam1911]

They don't drill the rear block, either

OOOhhh. So they have "virgin" rear blocks/trunions, not surplus/tear-down parts. I guess it's good to be the original manufacturer! LOL!

Cool, and thanks for the info!

-Sam

 

[THE DARK KNIGHT]

Yup, pretty cool. Though I have to say I'm QUITE fond of the AKS-74U that my build-buddy did off a complete, perfect (apparently unfired) kit. Just gorgeous!

Oh hell yeah a regular AKS-74U would be the best if I could find one cheap and escape to PA one day. But all the ones I see are a lot of cash Meanwhile draco is like $350 for gun - $200 tax - $250 on stock kit / mags / usa trigger group if the foreign one sucks / nice wood handguards

 

[Sam1911]

Oh hell yeah a regular AKS-74U would be the best if I could find one cheap and escape to PA one day.

Oh it's worth it, especially if you've just GOT to have about one of every Kalashnikov variant made! (As he does ... I can see the benefits to the bachelor life, sometimes!) LOL! Imagine my glee that he lusts after my "plain jane" AKS-74 we/I built in his shop.

Escape to PA? Did that. It's nice!

-Sam

 

[THE DARK KNIGHT]

Yeah they are sweet.....

 

[nalioth]

Well, I was gonna add to the other post, but you guys are too quick

This shows the factory Draco/Champion rear block. It is a virgin under folder block.


This is why I don't think the SBRs made by drilling and tapping the existing block are gonna be durable, as the area used on the block isn't made to support anything, but to keep the dirt and crap out of the insides of the gun.

 

[Sam1911]

Oh sure! All the strength is in the "ears" which carry the underfolder hinge barrel. Looks like maybe 1/8" of cast steel in the back plate. Not near the strength of the tang and stock tenon set-up of the AKM or the massive hinge and lock of the AKS version.

Very cool. And thanks again!

-Sam

 

[THE DARK KNIGHT]

So, drilling the stock block would probably not make for a good end result? May as well just change the trunion?

 

[Sam1911]

It depends on what you mean. If you mean drilling it side-to-side to make the proper sized hole in each of the "ears" and the receiver shell on each side -- to support a surplus set of under-folder parts, that'd be just perfect.

Nailoth is arguing against drilling and tapping the back of the rear block/trunion and screwing a stock attachment point to that. Look closely at smince's pic in Post 4.

I think he is, anyway.

EDIT: Also, compare Nailoth's pic of the Draco rear block to the one I posted of the assembled underfolder hinge. It's not just the big hole that they drilled. There are also four extra rivets (two per side) at the front edge of the trunion "ears." Not needed for the pistol where the trunion doesn't really do much but close off the rear of the receiver, but necessary when you're going to use the trunion to support a stock assembly.

And, there actually appears to be a 5th rivet -- or actually a bolt of some kind -- drilled through the very upper edge of the trunion, just where the recoil spring guide block slides in. You can see the pin is visible where the hole is cut out through the top of that slot. And the larger rear rivet is located farther back than on the Draco trunion.

-Sam