AR lower to MCX upper adapter thingy source? - Page 1

[ARCHIVED THREAD] - AR lower to MCX upper adapter thingy source?

Posted: 10/16/2018 5:24:32 PM EDT

Sig doesn’t have them apparently and it mucks up my plan to build a pistol using an inbound Virtus rifle upper and 6.75” 300blk barrel.

Posted: 10/16/2018 6:36:14 PM EDT

[#1]

If you bought the kit, it comes with an adapter.

Posted: 10/16/2018 9:35:45 PM EDT

[#2]

Another option https://www.knsprecisioninc.com/?s=Mcx
https://www.rainierarms.com/kns-precision-ar15-mcx-stock-adapter/

But be warned that the picatinny rail doesn't fully cover the rear takedown spring/detent hole. I think KNS is coming up with a wider picatinny rail section.

Posted: 10/17/2018 11:21:06 AM EDT

[#3]

Quote History

Quoted:
Another option https://www.knsprecisioninc.com/?s=Mcx
https://www.rainierarms.com/kns-precision-ar15-mcx-stock-adapter/

But be warned that the picatinny rail doesn't fully cover the rear takedown spring/detent hole. I think KNS is coming up with a wider picatinny rail section.

View Quote

That will work to get the MCX stock on the lower but it will not support the MCX upper correctly. That would be appropriate for a Faxon ARAK or a 22lr upper that doesn’t need the buffer tube. I would not use it for an MCX upper.

Posted: 10/17/2018 7:56:15 PM EDT

[#4]

They come from Sig, but currently are out of stock:
https://www.sigsauer.com/store/mcx-stock-adapter.html

Posted: 10/18/2018 8:49:02 PM EDT

[#5]

Dont know but I want one. Stupid sig wont make them.

Posted: 10/18/2018 11:10:19 PM EDT

[#6]

Quote History

Quoted:
Dont know but I want one. Stupid sig wont make them.

View Quote

Are you for real?

https://www.sigsauer.com/store/mcx-stock-adapter.html

Posted: 10/19/2018 5:52:48 AM EDT

[#7]

Out of stock, last I looked. And my understanding from reading the interwebs is that that has been the case for awhile. Really want to buy a newer Sig but this constant product churn makes me wonder.

Posted: 10/20/2018 12:22:54 PM EDT

[#8]

Quote History

Quoted:

Are you for real?

https://www.sigsauer.com/store/mcx-stock-adapter.html

View Quote

For real, theyre never in stock

Posted: 10/27/2018 3:42:19 PM EDT

[#9]

Quote History

Quoted:

That will work to get the MCX stock on the lower but it will not support the MCX upper correctly. That would be appropriate for a Faxon ARAK or a 22lr upper that doesn’t need the buffer tube. I would not use it for an MCX upper.

View Quote

I just did a check fit...and it does retain the bottom part of the spring plate but not the upper portion of the spring plate. Thus bearing surface is reduced to the lower portion of the spring plate...good/bad guess I'll find out. Anyway...I think it will work, and IMHO the KNS AR/MCX Stock Adapter is a viable option compared to the Sig adapter. I do have both...but I'm leaning towards using the KNS Adapter since it will allow me to use the lower on my AR uppers...while the Sig Adapter will not since there is a boss that will interfere with the operation of the charging handle on AR uppers.

Here are some pics of the KNS on an SBR lower:

Posted: 10/27/2018 5:13:23 PM EDT

[#10]

I wouldn't shoot it like that, without the proper adapter.

See the Nutnfancy retardation videos for reference.

Posted: 10/29/2018 7:38:38 AM EDT

[#11]

Quote History

Quoted:
I wouldn't shoot it like that, without the proper adapter.

See the Nutnfancy retardation videos for reference.

View Quote

Agreed. If that was a metal plate, maybe, but it's plastic; imagine the plate breaking and the springs shooting out, deflecting up, and skewering your eyeball.

Posted: 11/8/2018 4:42:00 PM EDT

[#12]

Hey I just posted in AR-15 asking a similar question. I then went and did a google search like a big boy and found a company selling something similar.

https://ddles.com/

Does anyone have one of these? I might get one.

Posted: 11/9/2018 1:39:43 AM EDT

[#13]

This should work and it is in stock https://www.rainierarms.com/kns-precision-ar15-mcx-stock-adapter/

Posted: 11/9/2018 7:00:24 AM EDT

[#14]

Quote History

Quoted:
Hey I just posted in AR-15 asking a similar question. I then went and did a google search like a big boy and found a company selling something similar.

https://ddles.com/

Does anyone have one of these? I might get one.

View Quote

That doesn't look like it's for the MCX.

Posted: 11/9/2018 7:00:59 AM EDT

[#15]

Quote History

Quoted:
This should work and it is in stock https://www.rainierarms.com/kns-precision-ar15-mcx-stock-adapter/

View Quote

That was discussed a couple of posts above, and general agreement was that this would not work well.

[ARCHIVED THREAD] - AR lower to MCX upper adapter thingy source?

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