They put a lighter spring for the sear?

Thats not s very good idea, don't know why they'd add that step. The lighter spring would/should increase sear wear, assuming its even strong enough to keep the sear catching in the first place. It would give you a lighter trigger pull, and if they are removing the return spring completely then that mod requires the r/t to function all the time, you can't run a stock trigger group without the spring unless you reset the trigger every time by hand.

Here the lack of a front spring is replaced by the extremely light weight spring, making is like not having it, but still providing a reset method other than the r/t which lets you still shoot mechanically rather than needing the pneumatic assist.

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98% of paintballers...eh, who cares