if you cut a spring, for the same length it will still have to work through, you'll make it STRONGER.
you can anneal them.
i am not sure to what specific hardness yours supposed to be. back from my tool maker times, we kept springs at about 50 Rockwell. springs are made out of special spring steel. they were brought up to about 870 C and dropped into room temperature oil. annealed to dark brown.
this is what i am referring to:
Stress Relief Annealing
Stress Relief Anneal
is used to reduce residual stresses
in large castings, welded parts and cold-formed parts. Such parts tend to have stresses due to thermal cycling or work hardening. Parts are heated to temperatures of up to 600 - 650 ºC (1112 - 1202 ºF), and held for an extended time (about 1 hour or more) and then slowly cooled in still air.