Builiding Registered SBR from an AK "pistol"

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Oh ok, I was confused yeah. I meant I was referring to "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." cause it looks from pictures possible to simply do that. Maybe even drill an extra hole in the front of the rear trunion on each side for a rivet for extra support just for the hell of it.
 
THE DARK KNIGHT said:
So, drilling the stock block would probably not make for a good end result? May as well just change the trunion?
Depends on what you want. For an underfolder, it's perfect (it's got an underfolder rear block that hasn't been drilled for installation yet).
For a side folder such as an Ace type, I'd recommend installing a fixed stock tang.

Sam1911 said:
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. ;)
Exactly.

Sam1911 said:
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.
That is a Yugo M70AB2 rear block. That isn't a rivet, but a spring loaded retention bar to keep the bolt carrier from flying out and doing damage when grenades are fired.
 
to keep the bolt carrier from flying out and doing damage when grenades are fired.

Oh. Yeah. I hate it when that happens!

(Where is that smiley with no teeth?) LOL!

-Sam
 
(Where is that smiley with no teeth?) LOL!

LOL

And yeah Nalioth I meant for underfolder, good to know it can just be drilled and installed. Dunno why but I just love the underfolder.
 
Excellent thread....Great info....Quick question....I have a Draco....Is it legal and "would it work" to drill and tap the back plate for a sling swivel post?...I'm not a builder but could have a local gunsmith install the sling attachment....thanks
 
FWIW, Rifle Dynamics and Red Stick (both AK builders) post regularly on the link I gave. Neither has posted any concerns about the back of the Draco not being strong enough for the folder.
 
Neither has posted any concerns about the back of the Draco not being strong enough for the folder.

Well, to be fair to them, it is a lot easier to do it that way. And if they go the extra mile and bolt it through with a nut on the inside, it could be better than a simple drill and tap job.

Not what I would want, personally, but it probably does help them keep costs down.

-Sam
 
Well, to be fair to them, it is a lot easier to do it that way. And if they go the extra mile and bolt it through with a nut on the inside, it could be better than a simple drill and tap job.

Not what I would want, personally, but it probably does help them keep costs down.
I don't know that either builder does it that way. It's my understanding that LMarshall73 did the comversion himself.

I was just stating that none of the builders came online and told him he was wrong to do it that way.
 
Well, to be fair to them, it is a lot easier to do it that way. And if they go the extra mile and bolt it through with a nut on the inside, it could be better than a simple drill and tap job.
If I did that I would want to at least weld the nuts in place; but personally what I would do (if I did the conversion) is cut a ≈ ¼ in. piece of flat stock to fit behind the rear of the receiver, weld it on, drill & tap and you're good to go.

:)
 
Is that simpler than replacing the rear trunion? I suppose if you count welding up the disused rivet holes, maybe it is. Of course, you'll end up having to try to weld the 1/4" steel piece, the rear trunion (cast?), and the sheet metal receiver at the same time, so you might want to take a couple of test tries at it.

-Sam
 
I'd have to look at mine to get a better understanding, but why couldn't you just grind off the back of the rear trunnion, then weld directly to the steel receiver? I imagine that the trunnion is cast steel (rather than iron), but it looks to be inferior quality to me, and still may be difficult to weld. I know that must be a big shocker...poor quality components on an AK? :what:
 
You might be able to do so. I had a buddy a long time ago who did a Tantal build "rivetless" -- by grinding a groove at each edge of the trunions and tig welding them to the receiver shell. I never got to see or shoot that gun, just heard about it. But I'd heard of it before, so he wasn't the only one crazy enough to try it.

-Sam
 
i was under the understanding that i was illegal to put a but stock on any gun that is registered as a handgun. I would think you would have to start out with a rifle reciever to do a short barreled rifle.
 
i was under the understanding that i was illegal to put a but stock on any gun that is registered as a handgun. I would think you would have to start out with a rifle reciever to do a short barreled rifle.

Nope. A Title I handgun may be made into a legal Title I rifle by the addition of a barrel of 16"+ and a butt stock. Of course, if you want to add just the buttstock and keep a shorter barrel, you'll have to register the weapon as a Title II Short Barreled Rifle.

Where the risky business starts is that the ATF reads that section of the National Firearms Act (1934) to say it shall be illegal to make a firearm of less than 26" overall length from a rifle.

SO, if you make a rifle out of your pistol (even once), it is illegal to then convert it back into handgun form, even using all the original parts, without registering it as an SBR. The ATF is saying, a rifle (even one that was once a pistol) cannot ever be anything but a Title I rifle, or a Title II SBR.

This is where the Mech-Tech carbines, and sometimes the Thompson Contenders, can get into trouble.

Pistol -to- rifle is fine. But it's a one-way trip. Rifle -to- pistol is NOT ok.

-Sam
 
Maverick223 said:
I'd have to look at mine to get a better understanding, but why couldn't you just grind off the back of the rear trunnion, then weld directly to the steel receiver? I imagine that the trunnion is cast steel (rather than iron), but it looks to be inferior quality to me, and still may be difficult to weld. I know that must be a big shocker...poor quality components on an AK?
Tromix makes back plates with the Ace pattern attachment holes already present. They are designed to be welded on the end of the receiver (with the tang cut), and make for a stronger receiver afterwards.
 
Why am I not surprised Tony has some cool trick for doing this? So, now I have to modify my NEEDS list to an ACE-stocked Draco SBR in .458 SOCOM. :D

-Sam
 
Tromix makes back plates with the Ace pattern attachment holes already present. They are designed to be welded on the end of the receiver (with the tang cut), and make for a stronger receiver afterwards.
...or just buy one of those.

:)
 
I just picked up a Draco yesterday, and ultimately I would like to turn it into something like this Photoshop'd SBR...

DracoUnderfolderSBR.jpg

Cheers! M2
 
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And I would advise those with (or wanting to get) a Draco to check the rear trunnion, as the CAI one I picked up on Monday is for an underfolder (it has the holes on the inside, and apparently would only need the outside of the receiver drilled once the appropriate SBR paperwork is obtained)...

Not sure if they all come like that, but I was happy to see it! :D

Cheers! M2
 
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