There is no difference between mild steel and 4130 as far as corrosion
resistance is concerned,

Now you have got my curiosity in gear. As I said, my personal experience is
that I have seen a significant differance.

I went looking for some quantized data on the subject. I have not found what
I was looking for on the net, and may run up to the University library later
on. For now I found
http://www.armycorrosion.com/summit2...PM/schario.pdf

It does not have much in the way of quantized data, comparing 1010 to 4130
corrosion properties, but there is enough to refute the claim that there is
no differance.

Anybody got a link that does a better job with this?