Thanks. But if I remember right oil tempered and music wire only require about 500 deg F for heat treating i.e. stress relief. You're probably right about getting a non-uniform coils, but most springs get non-uniform and develop a cant under normal springer usage.
I was lucky to find a suitable spring for my Daisy 130A. However, it's MUCH stronger than the original even after pre-setting it. I worry about internal damage the stronger spring may be causing. I'm even considering leaving the Daisy cocked for a week or so just to weaken the spring.
I realize it's more economical just to change out the spring. But, I was just wondering if it could be done at all. If so, it might be possible to recondition an old air rifle where replacement springs are no longer available. Of course, you could just wind a custom spring on a lathe, but that's a lot of work, too, plus you have to find good source of spring wire.
Anyway, I was just wondering what all the experts here thought.
George