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Lock Lever Tuning Spring

Lock Lever Tuning Spring

Regular price $5.99 USD
Regular price Sale price $5.99 USD
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This sear spring is manufactured as a direct replacement to the SIG factory part 1300857-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 a reduction to your striker lock lever's 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 the striker lock lever spring rate on a P320 means the trigger pull weight will be made lighter to truly customize your triggers behaviour and performance. The ISMI striker lock lever tuning spring is only available as a reduction rate.

NOTE: Sig Sauer classifies sear springs as consumable components where optimal performance will degrade at approximately 20,000 cycles, (for reduced spring rates this should be adjusted to approximately 10,000 cycles).


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