Super MPX SSA - M4 Curved Trigger

Geissele Super MPX SSA - M4 Curved Trigger

The Super MPX SSA was developed as a two-stage, high-performance trigger for the SIG SAUER MPX platform. Derived from our CRANE Safety Certified M4 carbine trigger, the Super Semi-Automatic (SSA), the Super MPX SSA offers the same performance, reliability, safety, and forgiveness as the SSA. The Super MPX is a non-adjustable, two-stage trigger that gives the shooter precise and accurate trigger control. The trigger is light enough for use in competitions, yet forgiving enough for demanding applications, such as dynamic, high-speed close-quarters combat scenarios. These features make the Super MPX the ideal trigger for competitions and target shooting, and make it the perfect trigger for your SIG MPX.

Geissele MPX Recoil Springs

Extensive testing of the MPX firearm system has shown that the bolt speed in these systems is very high. Geissele Automatics believes that the best way to extend the service life of the trigger and other operating components is to tune the recoil system with different spring rates depending on the type of ammunition used.

Geissele supplies the trigger with three spring weights: they are approximately 30%, 45%, and 55% stronger than the stock recoil spring. It is recommended that the shooter select the ammunition they wish to use and test the function with the included spring sets. To achieve optimal performance, the firearm must be equipped with the heaviest spring set without compromising full functionality.

To select the best spring, we recommend starting with the yellow spring set and testing whether it functions properly. To test, fire a 5-round magazine and observe the ejection pattern and whether the bolt recoils on the last shot. If this is successful, fire 5 magazines with 1 round each to observe whether the bolt recoils on the last shot. If the bolt does not spring back or if the ejection is weak, switch to the lighter spring set, which is marked in red. If the shooter feels that the system is still operating too forcefully, the functionality of the heavier spring set (marked in white) can be tested.

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