SIG MCX Zero Trigger – Flat
From: $259.99
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The short 2mm reset makes the Zero flat trigger one of the fastest on the market. The reset is also positive, which facilitates even faster shooting during training or competition. The trigger, hammer, and disconnector are EDM cut and then polished with brass wire to a micron finish in all critical contact areas for a frictionless engagement. The pull-weight and disconnector set screws are also welded after loctite for safety and a lifetime of use.
The Zero™ SIG MCX flat trigger pull weight is 4.5 lbs. They are available in Black Nitride. Black Nitride is a heat treatment process that enhances corrosion resistance, improves lubricity, and leaves a fine black finish on the surface of the metal.
In short, all of the features of the Zero™ trigger are designed to offer a shooting experience that is exceptionally smooth, crisp, and fast.
* NOT compatible with most AR-15 anti-walk trigger pins, including ours. Use factory pins or MCX-specific trigger pins. Compatible with our 45/90º as well as factory safety selector.
* NOT Compatible with Pistol Caliber Carbines.
* Compatibility is guaranteed only with the S-latch
* Primary tension screw: Tighten to 8in-lbs (no Loctite)
* Secondary tension screws: Tighten to 14in-lbs (add blue Loctite)
*Please allow 4-6 weeks for shipping on backorder items.*
- Short reset length: 2mm
- Forced reset: No
- Drop safe: Yes
- Design: Single stage drop-in trigger for the MCX platform
- Compatibility: Fits any MCX lower receiver properly machined to mil-spec dimensions
- Compatibility: All sig MCX platforms including the Spear LT
Frequently Asked Questions
To clean the ZERO trigger when the trigger is outside the rifle, we recommend using camp fuel or white gas. Fully soak your trigger inside a small container of white gas for about 5 minutes. Make sure the container is covered or has a lid. Use clean cotton patches to wipe off all carbon deposits from hammer, disconnector, and trigger.
To clean the ZERO trigger when the trigger is inside the rifle, we recommend using camp fuel or white gas. Place your lower receiver upside down where the hammer faces the workbench. Use a small squeeze bottle to squeeze white gas into the trigger. Repeat this step a few times until all surfaces inside the trigger housing are wet. Without any delay, rotate your receiver and use clean cotton patches to wipe off all carbon deposits from the hammer, disconnector, and trigger. Repeat this process until the carbon deposit is removed from the trigger.
If you chose to use lubrication after cleaning (not recommended), we suggest Hoppe's 9 Lubricating Oil (Model 30128). Only add two drops of oil between the hammer and trigger where the hammer spring is located.
All ZERO triggers are lubricated during assembly. We use Hoppe's 9 Lubricating Oil (Model 30128). This is the only time we add lubrication to the triggers. After you install your trigger into your rifle, we recommend that you not use any additional lubrication. All ZERO triggers are designed to function without lubrication (i.e., run dry). If you choose to run our trigger with lubrication, you must clean your trigger more often.
If you run your trigger dry, as recommended, you should clean your trigger every 800-1200 rounds, depending on the quality of the ammunition you run.
If you elect to lubricate your trigger, you should clean your trigger every 500-900 rounds, depending on the quality of the ammunition you run.
No, the MCX trigger is not compatible with MPX.
Yes, the MCX trigger is compatible with the factory SIG safety.
Yes, the MCX Zero trigger is compatible with our 45/90 safety selector as well as most aftermarket safeties.
The MCX Zero trigger was unilaterally designed by Blackout Defense to be compatible with the Sig MCX platform.
Both finishes are excellent, but the processes are very different and offer different benefits.
Black nitride is a heat treatment process that enhances corrosion resistance, improves lubricity, and leaves a fine black finish on the surface of the metal. Black nitride processing can reduce the hardness of the base metal by about 5 HRC, but it does not create any dimensional changes. Before black nitride processing, we heat treat (in house) our trigger parts to the maximum possible hardness—about 60-65 HRC for both A2 and S7 tool steel. The 5 HRC reduction caused by the black nitride processing is nominal and will not have any meaningful impact on the life of the trigger.
Nickel Teflon (comparable to NP3) is a plating of electroless nickel co-deposited with Teflon that provides remarkable lubricity and takes on the appearance of the base metal. Nickel Teflon application, does not involve heat and therefore does not reduce the HRC of the base metal, but it does create dimensional changes because it is a coating that is adhered to the base metal. Our trigger design accounts for these miniscule dimensional changes, and we also lightly sandblast the trigger parts before nickel Teflon processing to improve adhesion of the coating and to also offset its thickness.
The most impactful difference between the black nitride and nickel Teflon finishes is that nickel Teflon offers about 3x the lubricity—specifically, nickel Teflon offers a coefficient of friction of .1 (lower is better) whereas black nitride offers a coefficient of friction of .3. This results in a trigger with a smoother feel, which may make a difference for experienced and competition shooters.
We use full strength springs for all of our triggers.
Question
A Cordova –
Will this trigger fit on my sig m c x spear l t
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Blackout Defense –
Yes.
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Question
Jesse –
Will this work in the MCX Spear LT chambered in 7.62×39?
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Question
Kris –
Will you be manufacturing 3LBS triggers for the MCX anytime soon?
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Blackout Defense –
No. In our current trigger design the minimum trigger pull weight is impacted but the strength of the hammer spring. Our MCX trigger features a forceful hammer spring that limits the minimum pull weight to 4-4.5lbs.
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Question
Smith –
This might be a dumb question, but does the Mcx zero trigger fit the Sig Mcx Spear Lt, even though the Spear Lt is capable of using AR-15 triggers, because it doesn’t specify on their website what type of trigger, like drop in triggers of just the firing group. There has to be a reason why the AR-15 zero trigger and Mcx zero triggers are different products right?
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Question
Steven –
Does this work reliably with steel cased ammo (7.62×39)?
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Blackout Defense –
Yes. You could also select our AR-10 trigger for that ammunition.
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Question
George Shanafelt –
I am looking for one of your triggers for ar9 platform?
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Blackout Defense –
We are working on an 9mm design.
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