[TheForge] Spring steel Gun Part

[Dave Kammer]

Can anyone give me some advice on how to impart flexibility or spring to a small steel part. I have a rather old shotgun with a broken hammer spring. I am unable to find this part, so I made one from the steel handle of some old aviation snips. The part fits perfect, but after you cock the hammer a few times, the spring just starts to bend instead of springing back. 
  Can heat treating or tempering make the part more springy?