M*CARBO Brotherhood

AR-15 Buttstock Adapter For Your SUB-2000?


My opinion is that trying to get an AR stock on there is too much PITA and still not likely to work well (still got to be able to charge it, etc.).

I think a butt stock replacement for the current piece, perhaps with the possibility of mag storage and/or the ability to accept magpul butt pads or plates would be a more effective and workable solution.



Here’s my stock replacement for my Sub. First thing is removing the foam padding. I’m going to file the inside out to fit over the entire tube of the Sub. Once that is complete I’m going to dremel a slot on the bottom to match the Sub for the bolt, cutting an opening in the back for buffer, and drilling a hole for the pin. Looks like I will be able to slide Ace tube over the Sub tube and secure with the Ace front retaining mount and Kel-Tec pin before reattaching the Ace stock to the Ace tube.


I got a little bored and wanted to try to get better a 3D modeling. So here is this…

It’s a one-piece buffer tube for our Subs. It pins in the same and replaces the existing buffer.
You would have to machine a pin that sets flush in the tube, the stock will stop it from sliding out.
Also, the front sights won’t allow it to fold. It could be made longer and notched for the sight.
But the stock would have to be notched as well.

If anyone with a printer wants to try it, let me know.

EDIT: I’ll just share the file here on Thingiverse

EDIT AGAIN: The file won’t be available for 24 hours, new user thing, I guess.


This is just meant to be a template to later be machined out of aluminium.
Please consider that 3D printed PLA may not be suitable for this application.
It may work, it may even work well, but I can’t recommend using it. Just saying.


This picture is what renders on Thingiverse, suppose that is what it will look like.

I printed about 1/2" or so to see if it fit the tube on my Sub and also a spare buttstock.
It was very snug on the tube and loose on the stock, so I made a few adjustments.

I don’t have the skill to make a decent print of this, but I was able to order it for $24.44.
Thingiverse has a “Order Print” button right on the page.

After I receive it and try it out, I can move on to the next step.


@ValorSolo don’t suppose you can design a one piece full length handguard for the S2K can you? That would be amazing! :grin::+1:


I will look into it. I love this CAD stuff.