Somewhere in my faltering memory is the notion that CSMC originally used a coating rather any normal blueing process. I think this process was used on production models but then changed to Belgian Blue. My gun is in the 5XX range and has a very flat finish. It proved to be susceptible to staining from blood. No sign of corroison but rather a stain.

Last edited by QTRHRS; 02/14/08 03:29 PM.