Gunsmithing Cerakoting and Nitriding?

[lead ƒarmer]

Hey all, I am having a custom gun built right now and I told my smith that I would like to finish the action/barrel in cerakote to match my stock. He said he could definitely do it, but his opinion was that it is much better to salt bath nitride the barreled action. He said that with a custom action, the tolerances are so tight that any cerakote will have a tendency to make it sticky and not cycle smooth. I am not very interested in the nitriding because my caliber is not hard on barrels, I'm not fond of the black finish, and I'd rather spend my money on a cerakote finish. I have never had a gun cerakoted, so I am asking you guys with experience what your opinion is. On a custom action is cerakote a bad idea? What if I tell thim to not touch the bolt body? Thanks

 

[blurry6]

I think you're on the right track - if he's that concerned with function have him avoid the bolt body and do just the shroud and knob. I durakoted a rifle in the same manner and it looks and functions great.

Ry

 

[Twisted]

I've Cerakoted a lot of bolt guns including bolts. There is definitely areas that you want to hit carefully and do a little lighter than others, but overall never an issue with it. I will be doing a complete Cerakote job on my personal rifle in the next couple weeks pending it getting back from the gunsmith.

 

[turbo54]

Having had a cerakoted action that was sticky, as well as SBN treated actions, I agree with your smith, that SBN is superior.

You can cerakote over metal that's been SBN'd, but obviously that doesn't address the binding issue.

Obviously, thousands of actions have been cerakoted without causing binding, so most have plenty of clearance. What action have you got?

 

[mkollman74]

I'd tend to consult with the action manufacturer. Some will tell you to stay away from SBN as it will void any warranty the action may have due to the heat involved with the process. Another option is IonBonding, which is performed at much lower temperatures. In any case, I would reach out to your action manufacturer and see what they have to say on the topic.

I had my Badger M2008 done with the IonBond, and I love it.

 

[turbo54]

Every action manufacturer will advise you not to SBN, as the manufacturer wants to avoid any liability.

 

[lead ƒarmer]

Thanks for all the help guys, the action is from Defiance Machine

 

[mkollman74]

Every action manufacturer will advise you not to SBN, as the manufacturer wants to avoid any liability.

An assumption, but probably an accurate one. These guys do want to stay as far as they can from any liability (and frankly, I can't blame them any in today's business/litigation environment). Have you SBN'd a Defiance Turbo?

 

[turbo54]

An assumption, but probably an accurate one. These guys do want to stay as far as they can from any liability (and frankly, I can't blame them any in today's business/litigation environment). Have you SBN'd a Defiance Turbo?

I agree, you can't blame the action manufacturer at all. The SBN process is out of their control, but yet they'd be the first entity sued if something bad happened.

No, I haven't done a Defiance. I've done an FN SPR and a Savage Model 10.

I was able to directly confirm the Savage was 4140 steel, but I had to "read between the lines" to determine the SPR was the same (4140). I have a good understanding of metallurgy and heat treatment, so after measuring the hardness of my actions and looking over the phase diagrams of 4140, I decided to give it a go. So far so good. One thing I was worried about was the concept that bolt lugs and receiver lugs should be of a different hardness spec, or they are prone to galling. I am not seeing this at all, and I have ~1500 rounds through the SPR, and ~500 through the Savage. Everything is good to go.

I didn't measure/indicate my Savage pre/post-SBN, but I did for the SPR, both before and after, and didn't have any (detectable) dimensional change.

The SPR action cycled smooth and nice before SBN, but the Savage was - well, a Savage. Not "bad", but not sweet either. The SBN made the FN a little nice, but really improved the Savage a lot. The finish is extremely scratch resistant and very difficult to get it to rust. The barrel on the FN is stainless, and it has a few freckles of oxidation, meanwhile the action is totally good.

As long as the metallurgy is agreeable to SBN, I'm 100% for doing actions.

 

[masonjp]

I'm having my build currently being SBN. I'm betting its by the same gunsmith...in the portland area? After discussing my build with them I really couldn't see a reason not to do it. I also have a build done with a different gunsmith with a big horn action, and he also advised me not to cerekote it.

 

[Redcreek1]

Thanks for all the help guys, the action is from Defiance Machine

I've done Cerakote finishing on many Defiance actions and they are indeed very tight on their tolerances, relative to Rem 700's and some others and do require some extra care and effort in coating to accommodate. However, they are coated all the time with no binding issues when done correctly.

Cerakote is substantially superior to SBN in virtually all measurable and meaningful metric (based on independent lab tests) and comes in many colors.

 

[turbo54]

Cerakote is substantially superior to SBN in virtually all measurable and meaningful metric (based on independent lab tests) and comes in many colors.

That is a BOLD claim.

Please substantiate.

Several of my buddys have cerakoted rifles, coated by an extremely well respected (deservedly) gunsmith here on the hide. After a lot of use, the cerakote looks well used. Nature of the beast with a coating as far as I'm concerned. Meanwhile, my SBN guns look the same they did when they came back from the treatment shop.

 

[lead ƒarmer]

I'm having my build currently being SBN. I'm betting its by the same gunsmith...in the portland area? After discussing my build with them I really couldn't see a reason not to do it. I also have a build done with a different gunsmith with a big horn action, and he also advised me not to cerekote it.

Yes in portland, I take it you decided to go with the SBN?

 

[masonjp]

Yes in portland, I take it you decided to go with the SBN?

Yea I went with the SBN, not only does it have good benefits, but its also $50 cheaper than cerekote!

 

[blacktails]

Is the SBN finish only available in one color? Can someone maybe post some pics showing what the finish looks like? I haven't heard of SBN before, but if it doesn't wear like cerakote, I'm interested. Also, since I've accumulating parts for a build and still considering who to build it, and Portland is not really that far from me , can you share the name of the smith you guys are using, or PM me with it? I just read that Gradeous isn't taking anything new for 4-5 months, so unless I want to wait, I need another quality smith. Thanks.

 

[turbo54]

Is the SBN finish only available in one color? Can someone maybe post some pics showing what the finish looks like? I haven't heard of SBN before, but if it doesn't wear like cerakote, I'm interested. Also, since I've accumulating parts for a build and still considering who to build it, and Portland is not really that far from me , can you share the name of the smith you guys are using, or PM me with it? I just read that Gradeous isn't taking anything new for 4-5 months, so unless I want to wait, I need another quality smith. Thanks.

SBN = salt bath nitride = tenifer = melonite = ferritic nitrocarburizing = finish on a Glock, XD or Smith M&P

 

[Redcreek1]

That is a BOLD claim.

Please substantiate.

Several of my buddys have cerakoted rifles, coated by an extremely well respected (deservedly) gunsmith here on the hide. After a lot of use, the cerakote looks well used. Nature of the beast with a coating as far as I'm concerned. Meanwhile, my SBN guns look the same they did when they came back from the treatment shop.

As an example, in the ASTM B118 Salt Spray tests SBN in various forms had onset of rust within 200 hours and substatial rust by 400 hours. Cerakote exceeded 3,000 hours with no onset of rust and has exceeded 5,000 hours.
On the ASTM D-4060 Tabor Wear test, SBN finish withstood 3333 wear cycles and Cerakote withstood 6000 wear cycles.
Thats just two of the tests.
Not sure about your "buddy's" rifles, but thats not a scientific test run by independent labs.
All tests can be forwarded.

 

[Grott]

Red,

I think both finishes have there place but the two are not the same type of finish and can not be compared fairly. How will Cerakote do in the chamber or IN the barrel?
I agree to the test posted that in a salt spray test the exterior of a cerakoted rifle would fair better as it adds an actual film or coating to the surface.

What are the parameters of the Tabor Wear Test? Similar to the mechanical wear of the action cycling or the wear due to handling?

 

[Redcreek1]

Red,

I think both finishes have there place but the two are not the same type of finish and can not be compared fairly. How will Cerakote do in the chamber or IN the barrel?
I agree to the test posted that in a salt spray test the exterior of a cerakoted rifle would fair better as it adds an actual film or coating to the surface.

What are the parameters of the Tabor Wear Test? Similar to the mechanical wear of the action cycling or the wear due to handling?

Tabor Abrasion is a test using a weighted abrasive wheel that rotates at a constant speed to determine the resistance of finishes to abrasion wear, as stated by test standard ASTM D4060. Sven competitive finishes, including Cerakote H-146 Graphite Black, were tested in accordance with the ASTM D4060 requirements by Anachem Laboratories, Inc., El Segundo, CA. Each finish was tested three separate times in order to validate the test results. Panel weights and mil thickness were measured prior to the start of each test to determine a wear rating. A 1000 gram weight was placed on a CS-17 Tabor Abrasion Wheel as required by ASTM testing standards for testing finishes. Panels were cycled until the Tabor wheel wore through to the substrate. Finishes that required more than 500 cycles to wear through the finish to the steel substrate, were stopped every 500 cycles for the Tabor abrasion wheels to be cleaned. Cleaning the Tabor wheels every 500 cycles is a requirement to ensure accurate results. Once the Tabor wheel has breached the finish, the tabor abrader is stopped and a final weight is taken to determine the wear rating for each finish. Wear ratings are calculated by taking the weight of the test panel before abrasion and subtracting the weight of the test panel after abrasion and multiplying that by 1,000. That number is then divided by the number of cycles completed before the finish was worn through. The resulting number is the specified wear rating for that finish. This allows for factoring in the difference in thickness between the different finishes. Based on the ASTM Tabor test, Cerakote lasted nearly twice as long as the nearest competitor and 24 times as long as the furthest.

Because Cerakote has a nominal surface thickness of 1mil (.001) and is a spray application finish, it’s not suitable for inside of barrels like surface conversion bath finishes, such as the various versions of SBN.

I have sent a number of barrels out for SBN, as well as AR gas tubes, etc just to get the finish on the inside. I then do a light blast prep on the outside of the barrels to leave the SBN intact and Cerakote over it. That way you get the best of both worlds.

 

[Grott]

"I have sent a number of barrels out for SBN, as well as AR gas tubes, etc just to get the finish on the inside. I then do a light blast prep on the outside of the barrels to leave the SBN intact and Cerakote over it. That way you get the best of both worlds. "

That sounds sweet...nice hard finish and the color of your choice.

 

[USMC_0317_SS]

I've done Cerakote finishing on many Defiance actions and they are indeed very tight on their tolerances, relative to Rem 700's and some others and do require some extra care and effort in coating to accommodate. However, they are coated all the time with no binding issues when done correctly.

Cerakote is substantially superior to SBN in virtually all measurable and meaningful metric (based on independent lab tests) and comes in many colors.

I too have a refinishing facility where I use Cerakote exclusively. When dealing with an action that already hasd tight tollerances the coater must ensure equal application of the product and also ensure that it is not applied to thick. Cerakote reccomends .050" to .001" application thickness. Anyone familiar with custom actions knows that they are made very tight, but still not that tight, because they still must function. I shoot the product on at the lower end of the spectrum on the bolt and inside the reciever. The rest of the outter portions get the full mil or what I call mil + as I prefer to apply Cerakote a little thicker when applicable. As an experienced applicator this is completely possible, through practice and is realy the only way to apply Cerakote to a custom action or you will, in fact, get binding. I have done over 3K pieces and can attest that Cerakote is indeed a fine product.

 

[creids98292]

Quick note here on SBN, make sure you bolt handle is ONE piece or tigged on. You run the risk of the handle falling off in the bath, as most are around 1050-1100F. We use both with great results.
Chris
Benchmark Barrels

 

[turbo54]

Quick note here on SBN, make sure you bolt handle is ONE piece or tigged on. You run the risk of the handle falling off in the bath, as most are around 1050-1100F. We use both with great results.
Chris
Benchmark Barrels

Certainly worth considering.

I asked the SBN shop about this before sending my FN SPR action in, and they told me they'd done "thousands" of bolts with brazed-on handles and never had a problem.

I don't know if that's true, but I can say for sure that my bolt handle didn't come off during the SBN treatment.