When I arrived home today my mag springs had arrived, so I took one of my r9 mags apart and compared springs. The spring that has been loaded and unloaded ( I swap mags about every month) was one and a half coils shorter than my new spring. Now this is probably not enough to make a difference and I am not going to change at this point, but now, at least, I have spares and can change when I think it is needed. I remember reading a little about the metalurgy of springs in some mag a few years ago and it seems that the springs have "memory" and are able to work for years. It seems that single column springs are a little better at it than the double column style. It was noted that someone found an old gi 45 that had it mag loaded for like 50 years took it out and it functioned perfectly. The whole intent of this post was the fact that I could not get a spring from the manufacturer and now they did right and actually went out of their way to get them for me. This topic has been very interesting.