Why are guns blued?

countryfied252

New member
I was just wondering. Why are guns blued instead of being painted? Does it have something to do with the paint being heated or does blueing hold to the metal better than paint?
 
you telling me youd buy a painted gun over one in colt royal blue? Paint doesnt hold up very well, it chips off, scratches off, melts and bubbles with heat. Just doesnt adhere to metal well although i have a saiga 308 finished with some black russian paint they put on all of them. I may go duracoat or cerakote one day for that. Ive been told that blueing is a form of controlled rust. You are preventing the metal from tarnishing by.... tarnishing it yourself which i cannot understand because ive seen rust form on blued guns in moist weather. I go stainless on all my guns if i can get it personally.
 
To serve and protect

Bluing is just a coating to protect metal surfacecs. It's been around for hundreds of years as well as other metal coatings. Only in recent years have we seen powder coats or as you say, paint. I think you will see more of these in the future, as they improve. You may recall seeing chromed finishes until they ran into enviromental issues, in the USA. ... ;)

Personally, there is nothing more beautiful than a deep, high polished blue. .. ;)

Be Safe !!!
 
Keep in mind that you have tolerances on guns with moving parts that are in thousands of an inch and must be held for functionality. Coatings such as paint whether they be polymers, epoxies, anodized or powder coating are by there nature at min .006 - .008" and I mean the least. The process of prepping and applying mean machined surfaces must be etched or profiled for adhesion and applicaiton must be tailored to maintain breaks or lines where the coating does not interfere with the slide, cylinder mechanism or whatever riding surfaces.

Bluing works because it can be applied without all the crap noted above and because the process can be customized for color and appearance such as early Colts and S&W's. Finally bluing yield an excellent surface for lubricity an element absolutely necessary for guns to function
 
Many military guns have been painted (e.g., by the British and French) because it was cosidered better and less time consuming to apply than bluing. One of the main reasons paint is used today by many gunsmiths who used to do bluing is (ready for this?) the government. OSHA has put so many restrictions on bluing because of the dangerous chemicals involved that small gunsmiths just can't do it any more, so have resorted to paint of one kind or another.

Jim
 
Bluing also acts to protect the bare metal surface from rust (to some extent) because bluing is itself a form of rust (oxidation).
 
In the beginning of firearms, they were simply bare metal which rusted.
In an attempt to protect the metal better, browning was developed, which was not much more than rust that was smooth and formed a somewhat protective coating.

In the early 1800's a controlled form of rust was developed that was a blue color instead of brown, and offered more protection and was faster to apply.
There are a good number of methods of bluing metal, some more protective than others.
Prior to WWII a new form of bluing using hot corrosive salts was developed that allowed faster more durable bluing of guns and that's what's used today.

Modern hot salts bluing is a more blue-black in color, is fast to process, and offers reasonable protection, although it rusts rather easily and wears off from handling.
Today bluing is used mostly because it's a traditional gun coating that's an attractive finish.
There are much better gun coatings available, like hard chrome, the various epoxy based "paint" types, ceramic based paints, and polymer coatings, among others.

In early WWII the French, Belgians, and British discovered that a baked-on coating of enamel paint was a surprisingly durable gun finish and they used it for rifles, submachine guns and machine guns. Some pistols were also given paint or black colored lacquer finishes.

Today, there are a number of different paints that are very durable and wear resistant including the epoxy paints like Lauer Duracoat and epoxy paints with a ceramic additive. Many of these are more durable and more rust resistant than gun bluing.

Again, these days guns that are blued are mostly done because of the traditional appearance, and low cost per unit.
 
For many years in the 1800s virtually all US arms were left "in the white" with no metal treatment other than a coating of oil.
 
Coatings such as paint whether they be polymers, epoxies, anodized or powder coating are by there nature at min .006 - .008" and I mean the least.

Cerakote recommends an optimal coating thickness of 0.5 to 1.0 mil if I remember correctly (.0005" - .001").
 
Cerakote film thickness ?

Cerakote recommends an optimal coating thickness of 0.5 to 1.0 mil if I remember correctly (.0005" - .001").

Half a thousandth is pretty thin to say the least. Do you know what the product is by chance ? Is it a true surface coating or some conversion coating or plating process because the film thicknesses you are referencing, and I believe you, are so unbelievable thin for an coating like polymers or similar that I can't hardly imagine the control process. Very interesting for sure

My response may be in error now that I look at your post. Are you saying
0.5" or .0005" ?
 
Bluing is used for tradition, appearances, and because it slows rust formation on the metal.
Bluing is just a coating to protect metal surfacecs. It's been around for hundreds of years
Caustic bluing has only been around about a hundred years. It is cheap, and it provides some protection against rust. Before that, there were other forms of bluing, primarily different forms of rust bluing (which is probably why caustic bluing is so common nowadays). Many, many firearms prior to the late 1800s were left in the white. The brown patina we associate with old firearms is rust. Nowadays, environmental protection and safety laws frown upon high pH waste being dumped in landfills and such.

Although paint has been used, it was generally not resistant to cleaning methods used, so it had to be refreshed often. After it has been chipped and repainted repeatedly, it looks like crap, and it interferes wit smooth operation of close tolerance parts. So people who care about how their guns look and function generally do not want paint.
 
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Bluing is not a coating... It's a finish. It's a form of oxidation. the metal is soaked in a tank filled with water, and salt peter. Depending on the ratio of water to salt peter, the temerature, and how long the parts soak will determine the color and quality of the blue job.

If wiped down once in a while the bluing will last many many years. Bluing will ahow holster wear on a working gun. (police officer, security guard, someone who trains a lot)

Bluing can be removed with polishing. A nickle plated, or chromed gun must be stripped before they can be blued.
 
A lot of blues can also be removed with plain old vinegar. This is one method that is often used on replica cap and ball revolvers to remove the blue in the process to "antique" them.
 
Its more durable, and it is a tried and true way of protecting the barrel from rust and corrosion.

An exception might be duracoat, and similar things like it. That is sort of paint but its some seriously durable paint.
 
As has already been mentioned, there are several forms of bluing, including the do-it-yourself kind in a bottle, which actually works pretty well, considering. One kind is sometimes referred to as straw bluing, I think it is, for small parts. I have no idea how it's done but the result is a sort of golden (straw) color, which is guess is why it's called by that name. I believe I've only noticed it on things like safeties on some pistols.

Some versions of CZ pistols come painted but I doubt you could achieve the same result yourself. Of course, cars have been painted for a long time and the finish holds up pretty well and much better than car finishes used to.

Browning, as was done in the 18th century on military arms, was not a natural process. That is, the metal wasn't just allowed to sit there and rust. It was a process that was undertaken by a unit armorer (for which the soldier was charged). It was in a sense a controlled natural process but apparently it was something that had to be repeated every year or two, judging from what I've read in old (very old) manuals and standing orders.

The beautiful finish on some firearms, like older Colt revolvers, for instance, is partly the nice bluing and partly the perfect polish of the metal before the bluing is applied. The better the finish, the better the scratches show.
 
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