I recently got my C9 and I can hear something sliding back and forth in the slide when I move it around. I noticed that there are 2 springs with the firing pin. One is wider and slips over the other. It sounds like the bigger spring is sliding back and forth over the smaller spring, is this normal? Next question, I have been wanting to practice porting a slide so I found one on Ebay to practice on. It is the older type slide with the fixed rear sights, does this slide fit the newer C9s as well? Thanks in advance!!!