ChuckS1
US Veteran
Just curious. I have two 5 screw revolvers where the blue has turned splotchy brown in places. What's the issue?
What causes the factory blue to turn brown?
- Thread starter ChuckS1
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ChuckS1
US Veteran
Just curious. I have two 5 screw revolvers where the blue has turned splotchy brown in places. What's the issue?
john traveler
Well-known member
To a large extent, hesco is right.
Gun bluing is a controlled oxidation or rusting on the surface of the steel. With proper surface preparation i.e. polishing, degreasing, proper bluing bath temperature, and sealing of the finish with preservative oil and greases, the end result is the desired beautiful blue that we want. However, if that blued surface is left unprotected, or the bluing bath temperatures are marginally correct, or the metal is then exposed to finger print moisture or humid air, the blue surface continues to rust and form iron hydrates, giving the characteristic brown. Once brown, it continues to worsen because hydrates draw moisture from the air and continue to rust. The best you can do is use solvents and preservative oils to rub down and remove the brown, and coat the surface to prevent further rusting. Old antique guns frequently show this progression from all blue to splotchy brown, and finally to the "patina" of continuously removed active rust and re-rusting from handling.
Gun bluing is a controlled oxidation or rusting on the surface of the steel. With proper surface preparation i.e. polishing, degreasing, proper bluing bath temperature, and sealing of the finish with preservative oil and greases, the end result is the desired beautiful blue that we want. However, if that blued surface is left unprotected, or the bluing bath temperatures are marginally correct, or the metal is then exposed to finger print moisture or humid air, the blue surface continues to rust and form iron hydrates, giving the characteristic brown. Once brown, it continues to worsen because hydrates draw moisture from the air and continue to rust. The best you can do is use solvents and preservative oils to rub down and remove the brown, and coat the surface to prevent further rusting. Old antique guns frequently show this progression from all blue to splotchy brown, and finally to the "patina" of continuously removed active rust and re-rusting from handling.
dfariswheel
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Age and lack of care.
Bluing is a form of controlled rust that's blue instead of red-brown.
If the finish isn't properly cared for, it will tend to turn brown. This is actually standard rust forming on the blued surface.
Once it turns brown, there's nothing you can do about it.
Any attempt to "polish it out" will only remove the brown AND whatever bluing is left, leaving bare steel.
Bluing is a form of controlled rust that's blue instead of red-brown.
If the finish isn't properly cared for, it will tend to turn brown. This is actually standard rust forming on the blued surface.
Once it turns brown, there's nothing you can do about it.
Any attempt to "polish it out" will only remove the brown AND whatever bluing is left, leaving bare steel.
