Sig MCX on FA M16 lower

NorwegianShooter · September 28, 2015, 04:33 PM

Hey. I got a couple of M16 lowers and I´m looking for the option to get at least one fitted with the new Sig MCX upper. I might opt for the SBR-option with either the sidefolder or the telescope stock. My question if really wether or not the Sig upper will run full auto seeing as it uses a different bolt carrier and being sold as civilian kits. Are the "retrofit to AR-lowers" kits already out there?

Skans · October 1, 2015, 02:05 PM

I would be skeptical of the legality of trying to make this work - if it requires modification to the registered lower, or even modification to the parts in the registered lower, I think ATF may frown on this.

Theohazard · October 1, 2015, 06:36 PM

The OP lives in Norway, so I don't think he cares what the ATF thinks.

His question is a technical one, not a legal one, and it's one I don't know the answer to. I'm off today, but next time I'm at work I'll take a look at the bolt on our MCX and see if I can figure it out.

NorwegianShooter · October 2, 2015, 08:46 PM

I appreciate that.

I´m a registered collector, and they are part of two complete, unissued M16A1s. So no, I don´t really care about the ATF. We have our own problem over here, and they are called POD

I don´t want to use the original uppers I have. I could just buy a standard AR upper, but where is the fun in that? The MCXs look cool.

9x18_Walther · October 2, 2015, 11:26 PM

Quote:

I´m a registered collector, and they are part of two complete, unissued M16A1s.

Very jealous right now.

Theohazard · October 5, 2015, 11:33 AM

Sorry, OP, I forgot to tell you that when I went back to work we were sold out of MCXs. I'll try to remember to take a look at the next one that comes in.

NorwegianShooter · October 6, 2015, 01:17 PM

I appreciate it a lot. As far as I know, there is not a single MCX in my country so I have no way to check. If I am to go through the whole deal of importing, I really wanna know all the details beforehand, as you can understand.

I´m in a good position of having a collectors permit. You deliver a list to the authorities specifying the theme of your collection, and I get to purchase 25 weapons at a time within that theme (they can all be select fire if I choose). My theme is cold war, and there is a lot of goodies to track down. The limit is money really.

Theohazard · October 17, 2015, 02:08 AM

So we got a couple more MCXs in and I checked out the bolt carrier on one.

Unfortunately, it won't work with an auto sear; the rear of the BCG that would trip the auto sear is completely removed on the MCX.

NorwegianShooter · October 18, 2015, 10:59 AM

Thanks a lot for looking this up for me, even though the results were negative.

Back to the think tank I suppose... I really wanted something with a folding stock :P

Arizona Fusilier · October 20, 2015, 07:07 PM

The MCX wouldn't be Cold War....

dakota.potts · October 22, 2015, 02:37 PM

The MCX may not be cold war, but the original M16s are and I imagine the MCX is a non-regulated or less-regulated firearm which OP is trying to piggyback off of his Cold War themed registered collector's pieces

September 28, 2015, 04:33 PM	#1
NorwegianShooter Member Join Date: March 18, 2014 Location: Norway Posts: 80	Sig MCX on FA M16 lower Hey. I got a couple of M16 lowers and I´m looking for the option to get at least one fitted with the new Sig MCX upper. I might opt for the SBR-option with either the sidefolder or the telescope stock. My question if really wether or not the Sig upper will run full auto seeing as it uses a different bolt carrier and being sold as civilian kits. Are the "retrofit to AR-lowers" kits already out there?

October 1, 2015, 06:36 PM	#3
Theohazard Senior Member Join Date: April 19, 2012 Location: Western PA Posts: 3,829	The OP lives in Norway, so I don't think he cares what the ATF thinks. His question is a technical one, not a legal one, and it's one I don't know the answer to. I'm off today, but next time I'm at work I'll take a look at the bolt on our MCX and see if I can figure it out. __________________ 0331: "Accuracy by volume."

October 5, 2015, 11:33 AM	#6
Theohazard Senior Member Join Date: April 19, 2012 Location: Western PA Posts: 3,829	Sorry, OP, I forgot to tell you that when I went back to work we were sold out of MCXs. I'll try to remember to take a look at the next one that comes in. __________________ 0331: "Accuracy by volume."

October 17, 2015, 02:08 AM	#8
Theohazard Senior Member Join Date: April 19, 2012 Location: Western PA Posts: 3,829	So we got a couple more MCXs in and I checked out the bolt carrier on one. Unfortunately, it won't work with an auto sear; the rear of the BCG that would trip the auto sear is completely removed on the MCX. __________________ 0331: "Accuracy by volume."

October 22, 2015, 02:37 PM	#11
dakota.potts Senior Member Join Date: February 25, 2013 Location: Keystone Heights, Florida Posts: 3,084	The MCX may not be cold war, but the original M16s are and I imagine the MCX is a non-regulated or less-regulated firearm which OP is trying to piggyback off of his Cold War themed registered collector's pieces __________________ Certified Gunsmith (On Hiatus) Certified Armorer - H&K and Glock Among Others You can find my writings at my website, pottsprecision.com.

October 1, 2015, 02:05 PM	#2
Skans Senior Member Join Date: November 20, 2008 Posts: 11,132	I would be skeptical of the legality of trying to make this work - if it requires modification to the registered lower, or even modification to the parts in the registered lower, I think ATF may frown on this.

October 2, 2015, 08:46 PM	#4
NorwegianShooter Member Join Date: March 18, 2014 Location: Norway Posts: 80	I appreciate that. I´m a registered collector, and they are part of two complete, unissued M16A1s. So no, I don´t really care about the ATF. We have our own problem over here, and they are called POD I don´t want to use the original uppers I have. I could just buy a standard AR upper, but where is the fun in that? The MCXs look cool.

October 6, 2015, 01:17 PM	#7
NorwegianShooter Member Join Date: March 18, 2014 Location: Norway Posts: 80	I appreciate it a lot. As far as I know, there is not a single MCX in my country so I have no way to check. If I am to go through the whole deal of importing, I really wanna know all the details beforehand, as you can understand. I´m in a good position of having a collectors permit. You deliver a list to the authorities specifying the theme of your collection, and I get to purchase 25 weapons at a time within that theme (they can all be select fire if I choose). My theme is cold war, and there is a lot of goodies to track down. The limit is money really.

October 18, 2015, 10:59 AM	#9
NorwegianShooter Member Join Date: March 18, 2014 Location: Norway Posts: 80	Thanks a lot for looking this up for me, even though the results were negative. Back to the think tank I suppose... I really wanted something with a folding stock :P

October 20, 2015, 07:07 PM	#10
Arizona Fusilier Senior Member Join Date: September 19, 2000 Posts: 1,082	The MCX wouldn't be Cold War....