M*CARBO Brotherhood

AR-15 Buttstock Adapter For Your SUB-2000?


A prime attraction to the AR style collapsible butt stock is the ability to vary the length of pull. There is already an adjustable feature to the S2K LOP. It simply requires disassembly and reassembly of the but stock.

The length of the bolt and the design of the recoil spring are also relevant. What about shortening the buffer tube and replacing the stock recoil spring with a shortened nested recoil spring. Then adapt the current buffer tube locking pin to one that can be compressed to allow the butt stock to move forward or back without taking the gun apart?

That would allow the gun to still fold and leave the serialized part intact. If one would satisfied with the three existing LOP adjustments to the butt stock, shortening the buffer tube and using a nested recoil spring would be unnecessary, leaving only a compressible locking pin as the newly designed component


I’m glad I am only a consumer and not a designer. Once you guys figure it out I want one.


Design some different butt stocks that fit on the current Sub2K platform and have everyone vote and then only make that one replacement…just a thought.


I will be doing the same when I get a free weekend !
The tube will be cut short, inside diameter will be enlarged , I will make a cut out in tube for all factory bits ( pin, spring cap/latch) and corresponding cut out on top of stock
I doubt it will be able to fold, but I don’t fold mine anyhow


Just be aware that you might not be able to get a good sight picture with that cheek piece if you’re still using the stock sights. Some people can’t even get their head down low enough on the bare tube.


I’m using a red dot anyhow , with and added riser
So I won’t be using the stock for a cheek weld.
Factory sights are rough with ear protection … constantly knocking them off


5 Bucks on ebay, a razor blade and 2 self tapping screws



I say build it with a mag carrier for or MP .40 mags ( I kno I know the glocks are more common it seems) . I love it for the AR15. Kinda bulky with a 30. The 20 looks the best (not pictured). I have no use for a 10.


I could see some sort of an AR style buttstock, not that I have a issue with the stock one.


What type of buttstock is this? Do you have a link to it?


We’re still kicking around the Buttstock idea. If we made one it would be machined aluminum and similar profile of the factory but set up to match the AR-15 buttpad bolt pattern and allow storage of an extra mag. Any interest in this concept?


Here is the crude prototype of the initial idea for an AR-15 Buttstock Adapter. It’s way to long at this point to be useful. To replicate all factory function the AR-15 Buttstock intended to be used would need to be modified for the sight to drop into. Also a hole would need to be drilled through the Buttstock for the Buffer Pin.



I really like the idea of extra mag storage! Excited to see what you cook up!


Good start to coming up with a new stock for the Sub2000. Keep thinking outside the box. you will get a working model then we will all want one. Keep up the good work Chris.:cowboy_hat_face::us:


After you come out with the flip aside optic bracket, I would not be adverse to removing the front sight to let it fold.


I don’t have any specific link, it is a FAB defense GL-mag. You can find them multiple places on line ranging from $60-$100. There are a few YouTube videos on them as well. A lot to f the big carriers also sell them. I like the notion of the Integrated QD on each side as well, if that might be an option when / if you develope a stock, I know you already made a QD ring but this would give a different point


My first thought was weight/balance ratio?

what would say a 22 round mag of 180 grain 40 S&W do to the balance and handling characteristics? Quite a bit of weight to add to the very end of the weapon?

I like my M*CARBO-Tec 2000 to be light weight! Any guesstimate of weight @all-aluminum but stock + full mag?

One of the great attributes of this platform is its “lightweight and balance/maneuverability”

For me I’d like to see Improvement upgrades concern sighting options, and cheek weld.maybe some type of clamp onto the bolt tube cheek riser?


I like it the way it is.


I saw one somewhere on a review of the gen 2 and someone had put a AR stock on his gen1 that he showed a photo of and it looked like he had just drilled the stock pin hole in it and put it on . I may try it this weekend as I have a lot of extra base model AR stocks lying around from some builds . If it works out I will post some pics and info on it


Why o why change the stock in the first place? We bought the rifle in the first place was the design & simplicity of the design. One other thought I have with the hinge mount is just drill & tap the top, this way you can install any size rail you want. If the rail goes bad just change it.
Some person said about sight height, I use a pistol scope w/high mounts on a QR rail mount.
If you put it back in the same place as sighting it holds right on.
I will take a picture of the mount & try to add it for people see.