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Next Level Armament NLA Sig Saure MPX/MCX 9mm Luger Barrel Adapter NLX659 Color: Black, Finish: Nitride, 15% Off and Blazin' Deal

Next Level Armament Barrel Adapter Sig MPX/MCX, 9mm, Black, NLX659
Next Level Armament Barrel Adapter Sig MPX/MCX, 9mm, Black, NLX659
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Next Level Armament Barrel Adapter Sig MPX/MCX, 9mm, Black, NLX659

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Questions & Answers
Dimensions?

Hey Josh, I just received mine and it didn’t fit over the bottom shoulder/ bottom thread, I just used some 100 grit sandpaper wrapped around a sharpie and proceeded to sand the inside of the narrow end of the adapter. Then used the stock a2 flash hider turned upside down and a rubber mallet to seat the adapter down onto the beveled edge. If all else fails you can just snag a thread adapter or buy a new barrel for In Lead We Trust. Honestly that’s what I’m going to do soon they come stock in 1/2x28 TPI with an optional tri-lug already milled into the barrel behind the threads.

by BigFitswell, Verified Owner, December 10, 2021
See 1 More Answer
Does this have the 25 degree taper to fit tight on the Sig MPX barrel with the 25 degree taper? Manufacturer Answer

Yes, our barrel adapter is designed with a 25 degree taper.

by Next Level Armament, Manufacturer, May 27, 2026
View All Q&A You Have a Question? Ask!
Customer Reviews
Helpful Negative Review
Do not buy for MPX by HB, Verified Owner, January 10, 2022
Adapter does not fully clear the threads on a Sig MPX barrel, so a muzzle device cannot fully screw on the barrel. Not sure what barrel this will actually fit. Go with the Midwest Industries muzzle device collar adapter instead (MI-MPX9MMS).
1/1 found this helpful
Most Recent Reviews
SIG TAPER BARREL RING- BEST by Mark Bolden, July 21, 2026
I’ve purchased these from other sources & most had the wrong profile, but this one was by far, the best I have tried. It functions exactly as it should & because it is beefier & has the correct taper it locks onto the SIG barrel giving you a solid se...
Read More...
Most Recent Reviews
Not for MPX by JLC369, Verified Owner, March 25, 2026
As other reviews have stated, this adapter covers most of the barrel threads on the MPX. I was only able to get about ½ turn of usable threads from my muzzle device.
Most Recent Reviews
Sig MPX 9mm by DR, Verified Owner, March 16, 2026
Did not fit my MPX. Took it to a friends machine shop and increased the diameter.
Most Recent Reviews
Allows for a lot more muzzle device options. by Jason, April 22, 2025
If you don't want to deal with trying to track down a tapered muzzle device for your MPX, this thing is what you need. Does exactly what it's supposed to do. No POI shift, solid accuracy, and the bore alignment rod is directly in the center of my s...
Read More...
Most Recent Reviews
way too small by Ur Mum, Verified Owner, July 20, 2022
Not sure if these are actually for 1/2-28 or what, but they don't even come close to fitting 5/8-24. Doesn't even get over the end of my taper adapter, much less make it to the threads it would still have to clear to reach the taper.
0/1 found this helpful
Read All 6 Reviews

We've got an AWESOME deal for you!

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Blazin' Deal
Prices have been cut drastically on this product as part of a special offer. These prices are so low that there's no double-dipping with coupons or any additional discounts, but you'll still get the best deal out there. This offer won't last long, so don't miss out!
Color:
Black
Finish:
Nitride
Gun Make:
SIG Sauer
Gun Model:
SIG Sauer MCX, SIG Sauer MPX

Code: 3TG-BRD-86TO-NLX659

MPN: NLX659

UPC: 793585909034

Blazin' Deal
List: $11.00Save 16%
$9.25

  • Next Level Armament NLA Sig Saure MPX/MCX 9mm Luger Barrel Adapter, Black, NLX659
  • LANTAC MPX 13.5mm Crush Washer, Black, 01-PP-1351-CRW
As low as $15.55
You Save Up to 14%
OP Bucks$0.13

Product Info for Next Level Armament NLA Sig Saure MPX/MCX 9mm Luger Barrel Adapter

NLA Sig Barrel Adapter- Ensure a secure installation of your muzzle device. We created the NLA Sig Barrel Adapter to complement our Sig 9mm Flash Hiders and Comps. Ensure a tight fit of your muzzle device with the adapter. Sig Sauer added a tapered end to their MPX and MCX barrels. This prevents the crush washer from seating correctly when installing a standard muzzle device. The taper can also prevent proper installation of a suppressor, which could create damage to your suppressor or a baffle strike. The NLA Sig Barrel Adapter fits on the end of the barrel (inner tapered end faces the barrel) providing a flat surface for the crush washer to properly function. This eliminates the need for indexing and/or applying a thread lock product to hold the muzzle device in place.image

NOTE: We include the adapter with our 9mm muzzle devices threaded for Sig barrels.

Specifications for Next Level Armament NLA Sig Saure MPX/MCX 9mm Luger Barrel Adapter:

Manufacturer: Next Level Armament
Color: Black
Finish: Nitride
Fabric/Material: 4140 Steel
Gun Make: SIG Sauer
Gun Model: SIG Sauer MCX, SIG Sauer MPX
Weight: 0.1 lb
Caliber: 9mm Luger

Features of Next Level Armament Barrel Adapter Sig MPX/MCX

  • tapered barrel adapter for MPX/MCX

Package Contents:

  • Next Level Armament NLA Sig Saure MPX/MCX 9mm Luger Barrel Adapter

What firearm models does the manufacturer say Next Level Armament NLA Sig Saure MPX/MCX 9mm Luger Barrel Adapter is compatible with?

The manufacturer suggests that Next Level Armament NLA Sig Saure MPX/MCX 9mm Luger Barrel Adapter is compatible with SIG Sauer MPX, SIG Sauer MCX

Next Level Armament NLA Sig Saure MPX/MCX 9mm Luger Barrel Adapter Orderable Models

List of Orderable Models

  • Next Level Armament NLA Sig Saure MPX/MCX 9mm Luger Barrel Adapter, Black, NLX659 , MPN: NLX659 , UPC: 793585909034 , Code: 3TG-BRD-86TO-NLX659
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Last updated 2026-08-02 UTC.