DLC vs Nitride

I'll second that ^. I have a DLC coated bolt carrier group for an AR that I wore the coating off of just hand cycling the bolt tuning the gas tube. No action spring, just back and forth with my fingers.
 
DLC is a coating. It's applied to the surface and doesn't change the structure of the steel it's placed onto. Diamond-like carbon-- really hard, really slick coating.

Nitride is a heat treat. Ferritic nitrocarburization. The steel is heated up and exposed to a nitrogen rich environment (salt bath is a common method). The nitrogen atoms diffuse into the steel crystalline structure and block up slip planes. End result is usually a .005-.010" thick super-hard "case" on the steel. What you have to watch out for, however, is that the temperature necessary to get the nitrogen to diffuse into the steel normalizes the inner material, making it potentially much softer/weaker than when it started... Too many different types of steels to cover them all. Some flavors of steel/stainless are not the greatest candidates for nitride. Usually best to let the manufacturer do it before they sell it to you.
 
I'm not aware of a reason that wouldn't work, but I'm not sure if you would notice much difference. Maybe maybe not. More of a price vs reward thing.
 
DLC is a coating. It's applied to the surface and doesn't change the structure of the steel it's placed onto. Diamond-like carbon-- really hard, really slick coating.

Nitride is a heat treat. Ferritic nitrocarburization. The steel is heated up and exposed to a nitrogen rich environment (salt bath is a common method). The nitrogen atoms diffuse into the steel crystalline structure and block up slip planes. End result is usually a .005-.010" thick super-hard "case" on the steel. What you have to watch out for, however, is that the temperature necessary to get the nitrogen to diffuse into the steel normalizes the inner material, making it potentially much softer/weaker than when it started... Too many different types of steels to cover them all. Some flavors of steel/stainless are not the greatest candidates for nitride. Usually best to let the manufacturer do it before they sell it to you.

Ferritic nitriding and ferritic nitrocarburizing are not the same process. Similar, but not the same.

Case depth can be as much as .040" depending on exact process used and time exposed to the nitrogen bearing atmosphere.

Normalization temperature for 4140 (one of the most common gunmaking alloy steels) is 1600° F, same alloy is gas nitrided at 920 - 950° F. Core hardness from prior through hardening is unaffected.
 
Here's a pamphlet that describes to you some of the properties of DLC from the site of Club Custom Guns which uses Ionbond DLC, as the pamphlet describes DLC provides for seven times less friction than untreated stainless steel and is one of the hardest coatings out there, it also absorbs oil and releases it over time . With nitride it depends on what type of nitriding process you are referring to there are several different out there with different properties; they can use different metals, i.e. chromium nitride, titanium nitride, ... some are achieved by salt bath nitriding, some by gas. I'm no metallurgical expert but DLC applied by an expert company has been the slickest, so far most durable finish for me to date. I don't care if the outside of my actions is necessarily DLC'd but the inside and bolt I prefer to have DLC applied to.
 

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With nitride it depends on what type of nitriding process you are referring to there are several different out there with different properties; they can use different metals, i.e. chromium nitride, titanium nitride, ... some are achieved by salt bath nitriding, some by gas.
Please stop giving advice about things you don't understand. Just stop. People who know even less than you do are going to assume you know what you're saying while those of us who know better just roll our eyes. The processes you're lumping together are fundamentally different from each other and no, I don't have the time or inclination to teach you why you're wrong.

Please stop. There's already a shitload of misinformation out there and you adding to it isn't helping.

I'm no metallurgical expert
That much is obvious
 
For all intents and purposes, it doesn’t matter whether you buy an action that’s nitrided (conversion + thermal effects) or Diamond-like Carbon coated (pure coating). Both of them are hard, slick, treatments that provide pretty good corrosion resistance and come in black and black. Both of them can have issues if they are applied poorly, both of them change color slightly as they wear with minimal change of functionality, both of them are very durable if applied properly.

If you’re buying the action with the treatment, get whichever fits your budget. DLC can be done to any steel alloy, so if you’re doing the treatment after buying the action just go with that. Nitriding should never be done aftermarket unless you know the exact steel grade and are a metallurgical engineer of some kind.

99.9% of the members here won’t notice anything but placebo if they go for one or the other.
 
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Nitriding should never be done aftermarket unless you know the exact steel grade and are a metallurgical engineer of some kind.

As far as I'm concerned any firearm part that is heat treated by anyone after it leaves the factory/OEM producer is worthless and I won't touch it with a ten foot pole nor pay one cent for it.

But what do I know?
 
As far as I'm concerned any firearm part that is heat treated by anyone after it leaves the factory/OEM producer is worthless and I won't touch it with a ten foot pole nor pay one cent for it.

But what do I know?

Not a chance in hell it keeps the warranty, no guarantee it doesn’t explode in your face. Minor concerns.

Nitriding in particular can fuck you over for thin parts due to warping and possible stretching from the compressive stress. Good fun.
 
Nitriding in particular can fuck you over for thin parts due to warping and possible stretching from the compressive stress. Good fun.

And depending on the thickness of said thin parts and the case depth achieved, you could have wiped out a significant portion of the core ductility and ended up with a brittle cracker.

I don't know what the fuck possesses people to read some internet brochures and then think they know what they're doing.
 
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Capture.JPG


Is this what you want?
 
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Please stop giving advice about things you don't understand. Just stop. People who know even less than you do are going to assume you know what you're saying while those of us who know better just roll our eyes. The processes you're lumping together are fundamentally different from each other and no, I don't have the time or inclination to teach you why you're wrong.

Please stop. There's already a shitload of misinformation out there and you adding to it isn't helping.


That much is obvious
Whty don't you enlighten the OP then, I'll gladly stop and desist to be silent and listen to the metallurgy guru and his vast experience. Spread a little of that knowledge that you insist you possess, it will be to all our benefit. Just claiming that you have no intention to do so doesn't show a lot of it. I for one would be very interested to learn, especially if I'm so wrong. This is actually not meant in a sarcastic way. All that aside fact remains DLC has performed better for me in any of the moving parts of my rifles.
 
Does anyone know anything about DLC coating a part that is hard chrome or nickel boron plated?

In general, stacking coatings is a bad idea. The exception are if the intermediate coating is needed so the final coating can bond properly to the substrate - for example, electroplating aluminum in zinc before nickel - but these exceptions are few and far between.

Those specific cases, I don’t know about the DLC adhesion to chrome but it’s probably not great, and NiB tends to flake off which will cause serious problems with DLC. I’d recommend just stripping the old coating first.
 
I have two bolt actions that were Nitride treated by the manufacturer and a JP LMOS carrier that is Nitrided and have to say they are the smoothest of anything else I have ever owned.
I don't have any DLC components or actions to compare to them but have owned Np3 and nickel boron coated carriers and would choose the Nitride over them.
I really need to get my hands on a DLC coated action to see if there is any discernable difference.