I have read several threads about this over on the smith and wesson forum and in other places. On the scandium-framed revolvers, problems with peeling of the clear coat have been reported with using Gun Scrubber, Hoppes # 9, Simple Green, sprays containing acetone, solvents containing ammonia, and sometimes just from holster wear.
Far and away the most complaints come from using Gun Scrubber or carb cleaner. According to the MSDS, the active ingredient in Gun Scrubber is trichloroethylene. Tetra Action Blaster also contains trichloroethylene and CRC Brakleen (non-chlorinated) contains acetone, as do most carb cleaners. The Shooters Choice polymer safe degreaser contains heptane and isopropanol while the Shooters Choice quick scrub contains trichloroethylene. Breakfree Powderblast contains methylene chloride.
Of note, Smith and Wesson apparently recommends using Breakfree CLP and nylon brushes only to clean the revolver. I wonder if that is because CLP causes no finish damage. Although this is not mentioned in the S&W manual, many people have said that the service reps tell them this when they call to complain about the clear coat finish peeling.
Brownells sells some clear coat heat cured epoxy spray finishes in a variety of colors including satin and matte finish clear. Some people have reported good success in refinishing their own pistols by this method. The heat cured epoxy spray finishes are what are being used by the manufacturers these days, with Gun Kote being a popular choice. My research reveals that methylene chloride or methyl ethyl ketone are used to remove heat-cured epoxy clear coats, so any solvent or spray containing this chemical will also probably strip the clear coat.
Accordingly, based on their chemical composition, I would avoid using Gun Scrubber, Tetra Action Blaster, Shooters Choice Quick Scrub, Breakfree Powderblast, CRC Brakleen and any other spray or liquid solvent that contained trichloroethylene, methanol, acetone, methylene chloride, methyl ethyl ketone, or ammonia. These solvents seem to have a higher potential of stripping off or damaging any clear coat, based on anecdotal reports and my research. I would also not use any bore cleaner containing ammonia, at least on any part of the revolver that had a clear coat.
Many people have reported no problems with using Hoppe's # 9 while others have reported problems. All the problems that I found with using Hoppe's were with the S&W scandium-framed revolvers, and there are suggestions of at least one 'bad batch' of clear coat due to oil contamination during the finishing process. Simple Green attacks aluminum, and the scandium-framed revolvers are an aluminum alloy, so I would avoid that as well
So after digesting all of these threads and reading the MSDS on a variety of spray cleaners, I think that using Breakfree CLP, Shooters Choice bore cleaner or the Shooters Choice polymer safe degreaser along with nylon brushes or other non-abrasive tools has the least potential to damage a clearcoat finish. Given that my Taurus 651 titanium also has a clear coat finish, I would follow these same recommendations for a titanium revolver as well.
If anyone has any additional data or ideas, I would love to hear them. An expert on metal painting using clear coat finishes would be perfect to hear from.
