Has anyone mounted a an aftermarket fixed stock to their MCX using either the folding knuckle from Sig or any aftermarket picatinny buffer tubes mount for Sig MCX/MPX?

If so could you please post a pic, I'm wanting to mount a PRS Gen2 stock to my MCX and worried about stock rotating as only thing holding stock in place is straight screw on the back that screws into buffer tube. No receiver for stock to line up with to keep from rotating.

Or some ideas on how to fix this issue. Haven't actually tried this yet, just doing some mock ups as I tear down to do some cerakoting on the MCX.

Thx in advance!!

Not an MCX but here is my MPX with the thorsden stock adapter.  It does not fold but is way cheaper than the SIG offering.  The buffer tube screws on and has a set screw that goes in the small empty channel at the bottom of the buffer tube threads so it wont rotate.  One consideration is the additional length that any of the MPX/MCX adapters will add.  Most find that a carbine stock fully collapsed or in the first notch are the perfect length.  Unless you are like 7ft tall, a rifle length stock is going to be too long.

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Thx for the photo. I actually have the PRS stock on it now and looking through my new vortex viper PST gen 2 just delivered today it feels pretty good. Eye relief is good and it is just comfortable.  I'm not 7 foot tall but I am 6' 4" so I think it is going to work.  The way I always set my eye relief is close my eyes shoulder rifle till I'm comfortable and then open eyes to see what my view is. Not saying it the right way just always worked for me.

My only concern is the stock rotating on the buffer tube, might not be a concern but I'll know more once I finish what I'm doing and getting to the range. If it is a problem and no solution I will go for a carbine adjustable stock.

BTW, how you like your Mpx carbine? What range you shooting? I also have an mpx that I mainly shoot suppressed with 4.5" barrel, also still have my factory 8" I swap back And forth but was thinking about getting a 14.5" or even 16" barrel for it. I like my 2 sbr's but I still like my long barrels more.My 300wm and 308 both have 24" barrels and currently building a 6.5cn with 22" barrel and of course my ar 16" barrels.

I bought it for PCC competition shooting so most of my shooting is up close.  I have taken it out to 50 yards or so and it shoots fine with a 20 yard zero.  I am actually looking for a 4.5" upper for this to SBR but other than ILWT it doesnt seem like a lot of people are parting with their uppers yet.  

What adapter did you use to run the PRS stock?  with the small set screw at the bottom of the Thorsden, the stock is rock solid

The Sig folding knuckle that came on my MPX PSB.