You need to change the springs.
There are two springs, the main spring and the valve spring. The main spring is between the bolt and hammer, the valve spring is inside the valve and pushes on the cup seal.
A heavier main spring will give you more velocity, a lighter main spring will give you less. A heavier valve spring will give you less velocity (yep, opposite of the main spring), and a lighter valve spring can give you more velocity. Don't go too light with the valve spring or you might open the valve when pumping back. Luckily the Talon is considered a standard Nelson type pump, so any nelson spring kit will work or can be made to work with out much trouble. Phantoms are also nelson type pumps, so they share the same springs.
David Johnson, AKA Fubarius.
Nunquam emere quid potes facere