Compression Spring Design
For those who know about compression springs.
My friend Mike just bought a recoil spring for his semi-auto pistol. Before installation he measured it at 5". He then installed it, cycled the slide a few times, removed the spring, then measured it at 4-1/2". When he told me this I was more than surprised by this.
I am a mechanical engineer with no specific training in spring design and operation. But for a brand new spring to "instantaneously" suffer 10% plastic deformation after just a few compression/relaxation cycles seems, well, ridiculous.
And I just read a post elsewhere where the writer stated that is "normal" for a recoil spring to "take a set" and become shorter almost immediately after installation.
So I'm hoping someone can shed light on this for me. Namely, is such behavior normal for brand new springs in general ??
Thanks for your help,
Carl