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Trigger Tuning Spring

Trigger Tuning Spring

Regular price $9.99 USD
Regular price Sale price $9.99 USD
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This trigger return spring is manufactured as a direct replacement to the SIG factory part 1301575-01-R and works in all P320 FCUs including: 9mm | .45ACP | .40SW | and .357SIG, for both Manual and non-Manual safety P320 models. 

** Springs purchased as individual parts (one piece per package) **


This SIGMECH | R Part (Replacement Part) from ISMI provides either an increase or reduction to your trigger bar return spring rate. Which is a measure of how much force is required to compress (or extend) a spring by a certain distance (in the P320 this will be from rest to the distance it takes for the sear to release the striker). While higher spring rates increase stiffness and require more force to compress, lower spring rates mean the springs are more flexible and require less force to compress. Reducing or increasing the trigger return springs' rate on a P320 means the trigger pull weight will be made lighter or heavier, to compensate for other modifications or to dial in the P320 to your personal preferences and truly customize your triggers behaviour and performance. The ISMI trigger return tuning springs come in three options: +10%, -10% and -20% (relative to the factory spring rate).

NOTE: Sig Sauer classifies the trigger return springs as consumable components where optimal performance will degrade at approximately 20,000 cycles, (for reduced spring rates this should be adjusted to approximately 15,000 cycles).


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