Case Hardening vs. Bluing

[montelores]

Can someone please explain how true case hardening holds up over time? How does it compare to bluing (or, for that matter, stainless steel)? Does it require special care, or is it a durable finish?

Thank you,

Monty

[bigbores]

I emailed Bowen Arms asking about building me a 5 shot redhawk with a Case Hardened finish, and was told that he would not caseharden a redhawk because the grip was part of the frame and the finish would not hold up there.
hope this helps

[montelores]

Yes, it does help. Thank you. I have done a little reading on the process, but I am curious about real-world experiences.

I am specifically interested in USFA's finish, the "Old Armory Bone Case" finish.

Thanks,

Monty

[jared]

I have a number of case colored firearms. Mostly Turnbull but there are some others in the safe too. The brilliance in the colors will fade slowly over the years depending on use an sunlight exposure, but it is a slow process.

One of my favorite CCH guns Is a Clements flattop .44 Special that had the CCH applied by Turnbull, who also does USFAs. I have had the revolver for 6 or 7 years I shoot and carry it often. It has killed a couple of animals, and has sent many thousands of rounds downrange. The CCH has held up as well if not better than the blue, and MUCH better than the finish on the aluminum gripframe.

The Case Coloring on my USFAs still look like new after several years. The only CCH gun that I have that is more muted is a 3rd generation New Frontier, but I am not the original owner so that may be how the finish looked from the factory. Colts of that generation are not know for having a real bright CCH.

In short as long as you keep the gun oiled the CCH will last you a long time and look good in the process.

[CraigC]

It's typically not as hardy as bluing but with the clearcoat that Turnbull and USFA apply (also finished by Turnbull) it is quite resilient. I've had this Ruger Bisley refinished by Turnbull through Clements for several years now. It's seen quite a bit of holster use and hunting duty. The bluing is worn on the grip frame from handling but there is yet no sign of wear on the case colored frame. Even the hammer and trigger show only minor wear.

I need some newer pics of this thing. Grips have been changed twice since this was taken.

[montelores]

Thank you for the responses. Good information coming from experience.

I appreciate it.

Monty

[Gary @ R&G]

depends on what you mean by "over time". If you look at vintage guns made turn of the last century it is rare to see one that the CCH has held up as well as the blue. CCH seems to fade over the years. Not sure if it is from enviromental issues, wear or a combination of both.

Since stainless is not a finish it is not really a fair comparison. Stainless is very durable and can be bead blasted or even scotch brited to clean up minor blemishs.

[joej]

I've been asking around now for several weeks about keeping a CH revolver looking good. So far I've come up with two definate practices to avoid. 1st is not to use petroleum oil on the CH and 2nd is to avoid as much as possible, direct sunlight. Sunlight will take many years to fade the CH - petroleum oil and rubbing/polishing the CH frame will fade the CH a lot faster. Turnbull recommends using a very small amount of G96 on the CH frame. The previous owner to my fine CH revolver used strictly ballistol, which is a no-no, so the CH protectorant that Turnbull applied is probably totally removed. Wish I had this little bit of knowledge before I put my money down.

[nonpcnrarn]

Maybe they should add a sunblock to the protectant. I am not being facetious. Could whatever they use in suntan lotion to act as a sun block also be added to gun protectant? I believe they add sunblocking agents to car wax to protect the paint. Maybe car wax should be used on the CCH parts. You would want a wax not a polish as the polish would be abrasive so as to remove oxidation.

[montelores]

Thank you, all, for the great responses.

From Wikipedia: "Case hardening involves packing the low-carbon iron within a substance high in carbon, then heating this pack to encourage carbon migration into the surface of the iron. This forms a thin surface layer of higher carbon steel, with the carbon content gradually decreasing deeper from the surface. The resulting product combines much of the toughness of a low-carbon steel core, with the hardness and wear resistance of the outer high-carbon steel."

It does state iron, and not steel, however, in the beginning of the process.

Why was this applied to firearms, when bluing was available? Did it require less maintenance for true "working" firearms?

Thanks, again,

Monty

[AxeHandle]

When we see "Color Case Hardening" I have reservations that it does not mean the same thing you read under the topic "case hardening." My turning point in understanding was the bit of information from a basic metalurgy class that mild steel without carbon added could not be hardened.. It needs carbon.. The addition of carbon to the surface via packing in carbon and heating to a high temperture provides a opportunity to surface harden things like plows and other tools... While I don't really have a clue as to the original intent of case hardening of firearm receivers it is logical that this characteristic would be valuable. Not sure that the current CCH provides anything other than color..

[Frank V]

A lot of people worry about how well CCH holds up & that's ok it's their gun. I have seen any number of nice old 1st gen. & some 2gen. Colts that the case hardening has faded to a "patina" I think some natural wear adds character to guns so I guess I don't worry about a gun fading as much as some do. However I can see someone wanting to keep their nice gun nice.
I wonder what the new S&Ws with CCH frames will look like down the road?
Frank

[CraigC]

Really depends on what it is but there's no such thing as "mild steel without carbon". By definition, steel is an alloy of iron and carbon.

Case hardening was/is a heat treatment process by which carbon is imparted to the surface of the steel or iron to increase surface hardness. Hence the name, "case hardening" in that the hard outer layer formed a "case" around the softer, more ductile center. This helped with wear where the internal parts contact the inside of the frame. This was especially helpful with the soft iron used in early revolver frames. It was not intended as a finish, the colors are a by-product that folks began to prefer the look of. Through experimentation manufacturers like Colt refined their process and thus sort of developed a trademark appearance. Other manufacturers used different method than bone charcoal, such as the cyanide process used on H&R shotgun receivers. Same result, different process, different appearance to the colors.

Case hardening is still used today and it's the same as the article outlined. Power Custom case hardens their hammers and triggers and I'm fairly certain that Colt's and probably USFA's are case hardened as well as any of the old guns that Turnbull and others restore. Not just colored. Colt case hardens their hammers and triggers, then polishes and blues them. Then for some dumb reason they polish the hammer sides white.

Doug Turnbull pioneered the process by which authentic bone charcoal colors are applied to cast frames such as on Rugers (like mine pictured above), without actually getting hot enough to harden. He then coats them with a clear lacquer which not only serves as a protectant but also deepens the colors.

[montelores]

Thank you for the informative responses. I appreciate the shared knowledge.

Monty

[cubrock]

I can tell you one thing that will take color case right off a gun and that is Flitz polish. Don't ask me how I know....