SIG MCX Zero Trigger – Flat

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.