My instructor at my gunsmithing school uses regular toilet bowl cleaner to achieve a french grey look. Most steels will look almost like stainless steel to a very light grey. This process will not work on stainless, Aluminum or Brass parts.
The process is very simple to do and takes very little and equipment to accomplish.
1. Preparation of the part or parts… Polish and prepare parts to a matchless finish, clean and degrease all parts completely.
2. Heat up a can or container of water to HOT.. Not boiling, just hot.
3. Place the part in the hot water for 30 seconds.
4. Remove the part and brush on simple household toilet bowl cleaner. Then allow it to hang or sit for 2-3 minutes with the cleaner on the part. Make sure you have nice even coverage of the entire part.
5. Re-emerge the part back into the hot water for another 30 seconds.
6. Now dip the part or parts in cold water to rinse them off. Then oil the parts completely and wrap them up and allow them to sit wrapped in oil for 48 hours.
After 48 hours you can unwrap the part or parts and if there is no rust showing on any section or the parts then you have successfully done a French gray finish. You may now properly clean the part or parts and reassemble your firearm.
