This power spring is both longer and stronger than the stock spring.
When you pull the trigger, the hammer will be forced against the valve
harder, allowing more air (or CO2) to escape.
Personal chrony tests are showing, on
average, an increase of 40-60fps.
Do the math. That can be over a 10% velocity increase just by installing
Please note that this spring will cause
your gun to use more CO2
(although negligible) and will require more force to pull the handle