AR-15 Buttstock Adapter For Your SUB-2000?


For sure! If Chris and the team want to do both an adapter and a straightforward replacement stock, I’m sure there are plenty of people who would have a preference. And either is gonna be an improvement over the stock…stock. Something like your AR adapter appeals to those who have plenty of stocks/a specific AR stock they really like, and shooters who don’t mind adding a little length (or really want/need the height and extra length).

Others, like us, might just prefer an improved and more ergonomic replacement. I don’t mind the cheek weld terribly (and it works for my 45degree offset crosseye dominancy solution–which lets me use the red dot with my dominant eye and irons with my other from the same cheek weld). But I’d still drop a pretty penny for something more comfortable and with improved utility.

Either one is gonna continue turning the Sub into a very different beast than the factory model, which is cool with me. It’s a neat and interesting little gun, and the weirder it gets the better haha


Dred and The Three Laws made some smart observations about the two earlier drawings I posted that got me thinking. So I prepared the additional drawing below that tries to incorporate the best features of the first two and address some of the points they made. I don’t know if it is practical to separate the upper and lower sections with an adjustable slide, but I also threw that in for consideration as there seems to be some interest in greater adjustability of the stock for a longer LOP than what is offered by the OEM version. An alternative to an adjustable slide would be to simply keep the bottom part short and then have extension adapters for the adapter for those wanting a longer LOP. That isn’t as wonky as it sounds since the extension adapter would basically be a secure tube within a tube.

Of course, any stock modification will raise the issue of where the shooter’s cheek ultimately will rest and how the adapter should account for that. I don’t know how you deal with that other than mocking it up and testing.


Why not make a new buttstock? An altered version of the strike industries viper or the minamalist buttstock maybe? Something that had rubber plating but small sleek and you still feel like it doesn’t turn your gun bulky.


First off, it’s possible I missed something I’ll admit I haven’t read the entire thread, but as far as I have seen I haven’t seen anything that works good that doesn’t involve modifying the tube somehow. With that piece being considered the firearm I think a lot of people want to leave it alone. I know the idea of this adaptor is so people have the ability to install the AR buttock of their choosing but it just doesn’t seem to be any reasonable ways to do that. I am onboard with an aftermarket stock for my S2K. Here’s an idea: as everyone knows the original stocks on the S2K’s come with only 3 positions which involves which involves removing a pin to adjust, a 6 position telescoping stock like that on an AR adjusted in the same way (a lever) would be nice. I like the idea of it being based off of MFT’s minimalist buttstock and also the ability of storing more mags on it. Redesign a piece that goes over the tube and attaches using the hole where the pin is that all allows a redesigned stock to be adjusted with a lever instead of removing a pin. The redesigned stock also allows the original locking mechanism to work. So pretty much the same except telescoping and a rubber buttpad.


So any new on who’s going to design this butstock seen alot of ideas someone make it

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Ok … just surfacing to report progress. I have none to report. I’ve altered my target 'cause I decided I couldn’t live with the wonky layout generated by the scope rings.

But, Sunday, some guy posting as casper3oaks over at the KTOG posted this:

Casper3oaks at KTOG

And I’m in. IMO the solution is elegant enough to copy. My test tube is currently honed out for an interference slip over and shortened. This morning I marked the tube where the front sight will stow. Once the access/stowage is cut, I will begin drilling the tube for the bolt retainer pin. The buffer tube will actually be fixed in place on the Sub 2k bolt tube with this pin ala factory buttstock, so … once the tube is drilled, the next step will be grinding the pin down near flush with the AR buffer tube.

Casper3oaks rounded the little tube side latch point and glued it to the AR buttstock to hold it in the folded position. I’m not sure I will follow the plan that far. I’m thinking that the ability to tuck the front sight for a nearly complete fold may serve my needs. If not, fixing the latch to the AR Minimalist stock will allow me to lock the stock using the 6 position adjustment.

Here is my dilemma. I anticipate ditching my irons when I install my M*Carbo Flip to Side Optic Mount. If I ditch the front site, I won’t need to stow it and I’ll be wanting a cutout free cheek weld platform. My plan is get the buffer tube cut and prepped but try to hold out finishing the cuts and glue on the Minimalist until my final sighting solution is settled.

I will cut the front off of the Minimalist stock to prevent interference with the charging handle. Hopefully I can retain the QD Sling Mount socket.

And Edit to Add: I’m working with a Mil-spec tube and stock. But, hindsight leads me to confirm that the honing process would have gone much faster had I chosen a Commercial spec tube and stock. The larger bore dimension on the Commercial would simply require less material removal.

Modifying AR Buffer Tube To Fit SUB2000

Exactly what I’m looking for in a replacement SUB2000 buttstock. Add a spare mag holder to complete the “foamer” effect. I’d preorder one today.


What’s that? I thought foamers were guys who freak out over trains. :grinning:


Yea. That’s us. Waiting for the next MCARBO part to come out. :crazy_face:



When I finish whitling away at the buffer, I will post pics and fitment details. IMO, if @ChrisNelson produces this part, for us - it’ll be win city. Sooo many differences in all of our setups, many of us will need to decide on our own mods to the polymer AR buttstock. I think offering a modified minimalist for us would be a great bonus.

But with the tube part, you could find yourself one of the kitchen sink buttstocks that will allow you to stash a handful of magazines behind a trap door or sump’n.


K … so … I am close.

I still need to shave the pin so the Minimalist can work past it. Even with the excessive LOP as photographed, I can tell I will like this setup.


First things first … why does Home Depot devote an entire aisle to hardware bits AND absolutely refuse to stock, sort, organize or give any indication that they might have any grasp of their inventory position. Yes, I hate it when I have to shop after my local Ace Hardware is closed.

Good stuff. She’s together and it feels better than anticipated. Cheek weld moved onto the comfy, cushy plastic of the minimalist. I haven’t cut a hole to stow the sight so she’s not closing completely. I will try to wait for the optic mount before deciding if the front sight stays.

Da pic:


Yes I prefer shopping at my local ‘Screw Palace’ as well (I mean Ace hardware, not the Bunny Ranch just down the road :rofl:)

The buttstock looks awesome!! Seeing it like that makes me appreciate the minimalist appearance more. I’d always envisioned something heavier/bulkier, even with spare mag holders. But this is swaying me. Great work👍


What’s the rifles overall length? We don’t want any accidental SBR’s

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@Matt … I will measure OAL, LOP etc. But, no worries 'cause it is longer now. Fully compacted it sits about a half inch longer than the extended factory buttstock.

I’m going to pull it down tonight for a full eezox treatment. I will photograph, detail decisions and hopefully convince @ChrisNelson to make up kits so everybody can have this goodness. He can put it in the development que for consideration after the optic mounts ship :sunglasses:.

Spoiler: it is as simple as modifying an AR buffer tube, manufacturing a replacement bolt stop pin and slapping on the buttstock of your dreams.


@Dred any further on your mods? It’s an interesting solution. I’d be interested in what MCARBO could do with it. You had to mod it to allow it to close right?

But I’d probably just be happy with a straight forward replacement stock. Could be tailored to the Sub–foldable, maybe raise the cheek weld a little, and store a mag. I’d totally put down cash for that.


Yes. Yes.

I love it. Snuck through an indoor range Monday and picked out my desired LOP. Then I brought her home and made a hole for the sight to tuck into at my predetermined LOP. Couple of minor points regarding this. I did not shorten the length of the Minimalist, but I could. At the most compact length settings - my recoiless charging handle was limited by contact with the bottom of the buttstock. I would have clearanced for the charging handle if I wanted to run it this tight, but at my chosen LOP, I can run the full length without interference.

I cut the top of the polymer, but I did not cut the bottom of the buffer tube. I’m not certain I will 'cause I also borrowed the See All night sight from my 12ga. The see-all is a zero electronics sighting solution that is very fast - it remains with the Sub 2000 and the plan is to donate the Holosun to the 12ga. The see-all is important here 'cause IMO, it can replace the Sub 2000’s irons. I’m thinking the irons will be jetisoned as soon as I get my optic mount - keeping them for now for the unwanted instance where I don’t have time to place the See-all on the rail.

I’m still going to break it, clean it up and show the guts - hopefully tonight. Frankly I didn’t want to do a detail strip/clean until after I cut the final hole. Bedliner touchup dried last night so I can break her down again tonight.

Feedback from the range is all positive. I deliberately ran 124g Winchester NATO 'cause it has buttstock printed my shoulder every time out. Well … the result was zero buttstock print with the improved shoulder engagement from the minimalist. I’m happy for the M*Carbo rear sight 'cause my cheek weld lands on the Minimalist which is approsimately .125" raised off the buffer tube - sight picture would have been difficult to achieve with the factory sight.

I’m calling it done and successful.


@Dred, can’t wait to see it!:stuck_out_tongue:

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This is what I came up with in a day I had to get ready for a PCC match, worked well enough and I’m not worried about being able to fold the rifle at this time as I will just be using for competition while I wait for a broken finger to heal enough that I can go back to my pistol.


Hi guys, glad ya like it! Here’s a pic of the buffer tube. Whole lot of filing by hand went into this!