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[Caliber 22]

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[JaceSpace1369]

If you install a heavier hammer, do you need to install a stronger spring as well to overcome the inertia of the heavier hammer?
I would think so but am not sure.

On my old m2 I installed a heavier hammer but kept the factory spring and didn't experience any drawback.

 

[Simplemann]

I installed a heavier hammer (2.5 grams) kept the factory spring as stated by JaceSpace and also had no issues.

 

[Stubbers]

You shouldn't need to increase hammer spring. Increasing hammer weight increases the momentum, decreases hammer velocity and increases hammer lock time, however the hammer energy (fpe) would remains relatively unchanged.

-Matt