Black finish for stainless steel?

[Bill_Rights]

I am in the process of buying a Ruger Mini-30, and I like that it is a synthetic stock/stainless rifle, for corrosion resistance. But I would like a matte black finish on the exposed metal. Don't you agree? Look:

So, I hear you can't just Parkerize stainless steel.
What do you know of or recommend? I guess I am willing to pay to ship the rifle to a specialist somewhere.... Or is this something that any local gunsmith can do in-shop?

I did a quick bit of web engine work. Came up with Robar (Phoenix, AZ I think)
http://www.robarguns.com/additional_finishes.htm

Blackening of Stainless Steel
Robar is able to blacken stainless steel through the use of oxidizing type blacking compounds. This process produces black coatings on stainless steel and alloy steels by a "conversion" process. The chrome in the stainless steel is involved in a chemical reaction with the oxidizers in the solution producing chrome-sulfide. The application of the black finish is dependent upon the surface treatment of the steel. Bead blasted surfaces will have a satin black appearance while a surface blasted with aluminum oxide will be matte in nature. Importantly, dimensional changes involved in blackening are extremely small, less than 0.0001 Mil. This thickness of the black oxide type coating ranges from 0.00006-0.0001 Mil depending on the type of alloy being treated. Blackening of stainless steel not only makes the weapon more attractive but adds to its corrosion resistance (96 hours salt spray per Mil-C-13924B) and aids in preventing galling, common in stainless steel guns.
Metal Finishing - Black Oxide & Parkerizing
Rifles & Shotguns
Barreled receiver $115.00
Barrel only $75.00
Receiver only $75.00

Robar sounds like the highest of high quality outfits. Heck, this is just a farm/truck rifle. Are there any cheaper alternatives? Any closer place? (I am in Virginia)

 

[delrey327]

If I am not mistaken caswellplating.com has black oxide kits for stainless for decent prices

 

[SuperBoomTurbo]

I'm a little late to the party, but I've used Caswell several times for oxide treatment on my knives. It works great and you don't have to have an electroplating tank. Preparation, of course, is hugely paramount.

Right now, I'm contemplating a similar treatment for a Tanfoglio Stock 2 10mm I have, as its the only 'nickel plated sissy pistol' I own, and I bought for the caliber, not the appearance. I love a matte black pistol, and thus I've ordered their stainless oxide kit two days ago. Here's to hoping it comes out as nice as it did with the knives. Be aware though, they have two different kits, one for hardened steel (tool steel, etc) and one for stainless steel. Both are 'cold' treatments.

My black oxide kit was their solution mixed with distilled water in a bucket for instance.

 

[IROCZ]

SBT, Can you post before and after pics? And describe or post pics? Thanks!

 

[MtnCreek]

I had a SS barrel and AR gas block/flip up sight blackened the other week. I don't remember the name of the product, but I do remember it was moly based. I had everything blasted w/ 60 grit AO and the finish matched other AR parts really good. I think I paid $75 for blasting and finish. If you need a little more info, let me know and I'll call my smith and ask him.

 

[Sheepdog1968]

Robar can do exactly what you want. I plan on doing the same thing for my stainless 45-70.

Reread your post. I don't know of anywhere other than Robar. Could always use DuraCoat.

 

[exospex]

There's always Salt Bath Nitride. It's expensive, but well worth it. It is way more durable than any other finish on stanless steel. We have a lot of stainless hardware for our military applications salt bath nitrided.

 

[SuperBoomTurbo]

Salt bath nitiriding needs to be done by a professional though. Back yard experimenting will end in burns and exposure to toxic nastiness. Yes, its far more durable, but if you have that DIY yearning, the caswell kit is by far the easiest method I've come across. I'm not knock Salt bath; in fact, I love the coating. But it is one of those things that you definitely have to outsource.

For the fellow looking for pics, I'll have to find the memory card with my knife making adventures. Get back to you in a few.

Edit: First picture is clean belt ground steel. Its a blank in progress of O1 tool steel, nothing fancy (just for demonstration purposes). My first oxide was with D2. I'm still looking for the pictures as my card reader is being fussy.

 

[SuperBoomTurbo]

Second picture is the knife just dipped into the solution. Per the directions, its one pint solution and 9 pints water. I didn't have quite that much solution left, so I used 1/2 pint solution and 4 pints distilled water.

In the third picture, you see the blade after just one minute of submersion. Caswell recommends no more than 5 minutes max in straight black oxide, but I've gone a bit longer in an acid etch/oxide blend at 15 minutes with a thick cut of Damascus (with a lot of trial and error prior to that). Anyway, back to oxide, this was a quick demo. Normally one would completely submerge the part so you get a complete treatment that's blended together, no splash rings or whatnot like in the third pic. I adjusted the bucket to lean the knife blank into it further midway into the process, which is where those funky rings came from.

After you get the color depth you want, Caswell supplies metal sealant for the kit you use. My first black oxide kit for carbon steel came with two quart cans of what I suspect is hydraulic fluid, at least it has the aroma and color. For a knife, its either a dunk or a liberal brushing with sealant. I used the little foam brush you get in a ten pack for a buck. I've also used cheesecloth, but the sealant soaks in real fast, thus giving you stink fingers for a few days (if you weren't wise enough to wear gloves first, my normal protocol, but I was doing this on the fly

 

[exospex]

I agree that SBN is a process left to the professionals. We don't do it in house. We outsource it to a company in Minesota called Flame Metals. They do a bang up job. It usually takes them about two weeks to turn it around. I think their minimum charge is $105 plus return shipping.

 

[jblackfish]

Bill Rights, That's a sharp looking Mini but I have to admit I'm a fan of all-black guns mainly to cut down on glare - it'll look better when you get where you're going with it IMO. Good luck.

 

[Lucifer_Sam]

So, those of you that have used the caswell black oxide kits, what do you think about the durability of the finish? How does it compare to other finishes as far as toughness goes?

 

[SuperBoomTurbo]

Black Oxide Durability

Sam, just for you I did some tests today for durability on black oxide (henceforth referred to as BO ) applied to hardened carbon steel. Using an ultra high-tech screwdriver, I scratched the H*ll out of the workpiece and found BO equivalent in durability to a good bluing/parkerized finish. It took around two dozen hard digs to finally break through the finish to scratch bare metal, however, the primary use of BO is actually for a rustproofing agent. That aside, it does give a nice semi-gloss black appearance which can be dulled down to near matte black via mediablasting your workpiece (prior to finishing).

I've ordered up a batch of Aluminum Oxide custom ground to go through my airbrush so I can do just this to a 'hard chrome' finish on my Tanfoglio Stock II 10mm, as I too prefer a black weapon. Let y'all know how it comes out when its done.

So far as ultimate finishes, I'd still go with salt bath nitriding. As I've only had this done on knives, I have no idea how that might affect internal assemblies and moving parts should it come off or come into contact with said parts. I DO know that its mighty tough with abusive treatment, as a hacker/chopper/slicer knife will see far more opportunity for damage than your average pistol/rifle, provided you're not in a war-zone. SBN is more than a surface treatment and is what a number of firearm manufactures use for their finishes. One such familar name is Glock, using the techno-term 'Tennifer' (as many of you know). The SBN actually changes the metal in the chemical process, but just like bluing, or BO in this instance, it can still scratch and scuff with enough abuse. For the good news, it is highly unlikely to rust, and with BO, its easy to refinish as breaking down your weapon and prepping the metal for refinishing just as it was with the initial treatment.

With my knives, BO will grind off with some effort. I've also torture tested Duracoat on knives and found that it didn't hold up for this particular application. Grinding it off cleanly does take a bit more work than BO, but thus far i haven't found anything that won't on the grinder.

 

[Lucifer_Sam]

Thanks for the info. I've looked at those kits before, but I wasn't too interested if they ended up with a finish that was something like a typical cold blue.

I'm actually planning to pick up one of those Tanfoglio 10mms myself, by the way.

 

[Stophel]

I wonder if you could cover it with 2400 and set it on fire? It sure makes durable black colors on the end of my S.S. S&W cylinder!

 

[SuperBoomTurbo]

Stophel, you might be on the right track. Add to that all the crazy chemicals I have sitting on my tool shelves and we'd have a heck of a coating. Or a puddle of molten steel, but here's to thinking positive!

Sam, I've heard the magazine issues have been resolved, but in the event you end up getting one that's been on the shelf awhile, you'd do well to replace the magazine springs first thing. Check out henningshootsguns.com for a nice selection of Witness parts. He stocks stuff mainly for the Elite series pistols, but you'll soon find why some call them 'The Italian Combat Lego'.

Accuracy is as good as, if not better, than a few $2k custom guns I've shot. If it had a rail, it would be my ultimate. Come on Stock 3!