Stainless Steel vs Treated

[kdude]

What's the pros and cons of Stainless Steel Slides and/or barrels? Example KAHR
Vs say Glocks Nitration Treated Slide and their Cold Forged Barrel?


Sent from my iPhone using Tapatalk


Sent from my iPhone using Tapatalk

[Alfonse]

I guess I'll start. Any treatment on steel will wear off at wear points. Those wear points will then be subject to corrosion just like untreated steel is. As far as a brand new, unused treated surface, a salt spray test is the best way to look at its inhibition to corrosion. Even galvanize will succumb to a salt spray eventually.

Stainless also comes in different susceptibilities to corrosion. For "marine grade" stainless, you are typically looking at something like 316 stainless. It is non-magnetic and very corrosion resistant but difficult to machine well and not as hard or strong as some other grades.

I believe kahr makes their slides of 416 stainless. It will corrode and pit if subjected to poor enough conditions. However, it will perform just as well as new even in an area with a scratch. A treated steel surface will not. It machines pretty well and can be heat treated to pretty high levels of hardness.

I have pistols with coatings by Beretta, Kahr (DLC black coating), and CZ. They all will wear or scratch and leave exposed steel (except Kahr which leaves exposed stainless). I expect Glock is the same.

Forging is a different issue. You can google all kinds of stuff on barrels and what is "best." They used to chrome line barrels to help protect them from corrosive powders. Forging is a hammering approach and can be used to both form the barrel and put in the rifling. There are several ways to rifle a barrel. They can be broached, button rifled, forged, etc.

I don't think you can tell the difference in a pistol. I know I can't.

Kahr does a pretty deluxe version of barrels on their pistols. The premium pistols are some sort of steel alloy that is machined by Walther and drilled and rifled to match specs after heat treating. They don't say, but it appears to be some sort of high strength stainless steel. The premium series have polygonal rifling and the others have standard rifling.

If you look at high end match rifles, Krieger, Criterion, etc. barrels are made in a similar way. Stainless are the most premium of even those.

All of that is probably poor cocktail party trivia, and would I bet make virtually no noticeable difference you could tell in a pistol. Well, you might notice the stainless versus coating thing. I have an easier time keeping a stainless gun looking good with use than I do any type of coated steel. But, that may just be me.

Best of luck with whatever you choose.

[CJB]

Forging is a different issue. You can google all kinds of stuff on barrels and what is "best." They used to chrome line barrels to help protect them from corrosive powders. Forging is a hammering approach and can be used to both form the barrel and put in the rifling. There are several ways to rifle a barrel. They can be broached, button rifled, forged, etc.

I don't think you can tell the difference in a pistol. I know I can't.

Kahr does a pretty deluxe version of barrels on their pistols. The premium pistols are some sort of steel alloy that is machined by Walther and drilled and rifled to match specs after heat treating. They don't say, but it appears to be some sort of high strength stainless steel. The premium series have polygonal rifling and the others have standard rifling.

If you look at high end match rifles, Krieger, Criterion, etc. barrels are made in a similar way. Stainless are the most premium of even those.



A few minor corrections and additions to Alfonse's comprehensive treastise.

Any barrel that has the word "forged" in its description of manufacture is hammer forged, which is the only way forged barrels are made. Forging is a process of using a hammer (or press) to work metal, which can be heated, or cold. The blacksmith made horse shoes from iron bar by heating it and hammering it to shape. A precision part is made in whats called a forging die, and is usually trued and further machined after forging. Heat treatment then follows.

In the case of hammer forged barrels, they start with a relatively short, fat blank. The blank is drilled, but not nearly so precisely as would be with cut (broached), or button rifling methods. After drilling, a mandrel - a pattern - that has the impression of the rifling on its outside, is inserted into the drilled blank. Then the fun starts. The blank is put into a hammering machine and in about as much time as it takes to chew some stale Bazooka gum into bubble forming consistancy, you got a raw hammer forged blank. The machine beats the living snot out of the barrel, making it long and thin and the full length of the mandrel (which was formerly hanging out at both ends). Kahr says they start with a three inch blank, and they "imply" that most of that is cut away to make a barrel. That is some marketing hyperbole. What is happening there is the barrel goes from being three inches to maybe an inch and three eighths or so in the hammer forging process. Then its machined to final profile, the locking lugs are machined, chamber cut, feed ramp cut, etc etc. Not Kahr, but other makers, will use a true cylinder for their barrel, and the locking end is formed (usually investment cast) and brazed or silver soldered onto the end of the barrel section, which is then chambered. This is found on Springfield 1911 barrels, some Sig barrels and others. Its a way to get the more time consuming part of the barrel made more quickly, then joined with the barrel itself.

By any means, heat treatment comes prior to finishing. I am not sure if Kahr uses stainless barrels. I do know the outside of the barrels are nickel plated, and this is most likely for lubricity and galling resistance against the slide and other moving parts.

The hammer forged blanks are provided to Kahr by Lothar Walther Co. (Lothar was one of Carl's sons, and I think... his grandson now runs the company, based in the US someplace....).

Will add too, what Alfonse said about making no difference..... totally correct. Talk of match target blah blah blah... is about as useful as stacking rat turds. Any slight variation you'd get in rifling type - with a pistol - is more than offset by other slop in the mechanism, such as slide, barrel and frame fit.

Companies try to impress that polygonal rifling is more expensive. They never really say it out right though. They'll talk about "expensive polygonal rifling", but then again, everything has an expense, so its a true statement. I cannot find anything, any shred of evidence, anyplace online, nor in any of my old school texts; nor has any industrially inclined member of my social clique been able to come up with a reason that polygonal rifling should be more expensive than traditional land/groove rifling patterns that are made by hammer forging. So put that thought out of your mind too.

Getting back to rifling hows - pistol barrels can be cut rifled, which uses a gang broach to do the cutting. Its a relatively slow method, but also well suited to small shops that have low production. Bar-Sto does cut rifling, and while their rifling is ok, its the outside of their barrels that make them what they are - the precision they use makes them fit very well. Another kind of rifling is button rifling, which uses a carbide "button" which is pushed through the drilled blank, ironing out its pattern into the drilled hole. Hydraulic pressure is used to push the button. Button rifling is cheap to do. It also puts many internal stesses into the steel of the barrel. In a pistol, those stresses are meaningless. Not so in a rifle. The pistol barrels that have their locking ends attached rather than built in, are most likely made from button rifled long blanks that are cut, and mated to pre-made locking ends. Then there is hammer forging. There is also an EDM rifling that is used... but the process is very, very slow. I've personally done a fair amount of EDM work, and the precision presented to the public is a false one. EDM is great for cutting negative images of positive parts. Mold making for injection molding uses EDM quite a bit. Here's the thing with EDM: Its slow as petrified monkey ***. And the electrodes wear out rapidly, no matter how you use them or what they're made of. Typically, to EDM a cavity for say.... a plastic gear used in an electric drill.... I'd start by hogging out the cavities, then use a series of electrodes (that I made one after another out of carbon, or sometimes brass). As each electrode wore down, it was used only for the first pass. Then #2 was used for an intermediate pass, then #3, #4, #5.... etc until the finished cavity was the correct size. Then #1 electrode was tossed, and the pecking order was moved one rung up the ladder, so #2 was now #1 and #3 became #2, etc. S...L...O..W! And... if you want a good surface finish, you have to go even slower. EDM is an erosive process. Think of it as sandblasting with an electron stream. You need a close fit and low current for a better surface finish, but even then it comes out looking like a fine glass bead surface, which means.... a barrel needs further polishing to get it looking and shooting right. Doing EDM barrels in a production environment.... I dunno... my hats off to whoever can make that work profitably, when there are so many other (faster, less costly) methods to use.

In short - stainless steel is good! You can coat it as you like with Ceracoat or K-Kote etc. Barrel fit on the outside is more important than barrel's rifling.

Kahr pistols use good stainless, and generally will out perform the capability of the shooters.

[TheTman]

The black coating on my M&P is put on over stainless steel, so if the coating does wear, corrosion shouldn't be a problem. I don't know what other companies do this. I would suspect that Glock might.

[Alfonse]

Well, a post on M4carbine.net claims Glock uses carbon steel for its slides, while S&W uses stainless. Both are finished basically the same way with nitrocarburizing or Salt bath ferritic nitrocarburizing.

I found it on the internet, so it must be.....

[jocko]

kahrs polygnoal barrels are made by Lothar. They come in 3 ft blanks and drilled and rifled when they get them, They cut the barrels into blanks and then the machine the chamber area and outside of the bbl. Then the barrel is sent off to a nickel plater. their regular barrels are made her in the Uj. S. buy a outside vendor and kahr does the above finishing work. Not sure of those barrels are forged or not. I am gonna guess even that the Lothar barrels which are German and with a stellar reputation of making great barrels, are probably not forged either.. Just sayin

The DLC finish on kahr slides is also a process that they do not put on their slides. It is an ouside vendor thing. It is rockwell hardness in the 60's that finish, so IMO its gonna takes some series holster usage to wear at the wear points even. U can google up kahrs DLC process and see how this is done even. Not just a spray and let dry finish, and I would be Glocks tennifer finish is very similar to. We are paying more for kahrs for some things that we take fore granite are of no expense to do..

[Longitude Zero]

Glock Tennifer shows visible holster wear but the finish is virtually indestructible. Bare SS is a cheap way out and shows wear almost instantly. IMHO bare SS is a take it or leave it proposition. Oh yeah I have seen SS rust. Don't make the mistake of thinking it cannot rust as it is after all steel.

[jocko]

A couple of years back Kahr decided to discontinue carbon steel guns and manufacture all slides and steel frames from stainless steel. Most consumers liked the corrosion resistance of stainless.
However, Kahr quickly discovered that not all consumers wanted bright and shiny guns. In dim light, the glint of a stainless slide being withdrawn by an undercover operative could lead to fatal complications.
To solve this problem and darken the stainless slide, Kahr flirted briefly with baked-on Teflon used by many manufacturers but found the results less than satisfactory. The economy of the finish was appealing to Kahr, but is soon discovered that the cosmetics were short-lived. Kahr tried another process that required substantial heat. This actually changed the metal's molecular structure and made it more brittle. Finally, Kahr developed its proprietary Tungsten Diamond-Like-Coating (Tungsten DLC), which uses a process called Plasma Assisted Chemical Vapor Deposition to coat the parts.
Tungsten DLC is applied in a vacuum chamber where cathodes transform the tungsten into a gas that plates the parts. The process increases the surface hardness to a whopping 90 on the Rockwell C scale. Just for comparison, your average 1911 frame will register about 28 to 30 on the same scale.
One of the best selling points of the Diamond-Like Coating in that the parts are never heated over 300 degrees Fahrenheit, so there's no need to worry about the parts losing their temper, softening, or becoming brittle. Also, only about two microns of the material is deposited on the slide. In case you're wondering, that amounts to about 80 millionths of an inch-far too little to affect the parts' function or fit.
Kahr's Tungsten DLC thoroughly impresses me. Not only does it perform its intended task of coloring the bright stainless steel to a matte, non-reflective black, it also provides a tough, corrosion-proof covering that is virtually scratch proof. And it will not wear even when subjected to extensive holster carry. For a gun that will be used exclusively for concealed carry, the Tungsten DLC finish makes a lot of sense


GET WELL MUGGSY

[Alfonse]

Okay Jocko, but I have a fairly recent DLC PM9 that has holster wear around the muzzle and on the top of the slide running back to the chamber. I bought it that way. It did come with two kydex holsters and the finish is gone from around the muzzle and the first part of the upper corners of the slide.

Get Well Muggsy

[Longitude Zero]

I would like to see a link that proves the 90 Rockwell rating by some organization other than Kahr. A 90 rating is almost as hard as I diamond and manmade processes that good I am skeptical of and require independent verification to believe it. Even the Kahrs with a black finish show holster wear. I have seen it firsthand.

[b4uqzme]

All I know is that I have 2 stainless Kahrs more than 10 years old. I bought them extremely dirty and neglected but they both cleaned up to look new. You'd be hard pressed to find a single mark. Both nickel barrels are perfect too. I can't ask for more.

Get well muggsy!

[jocko]

I would like to see a link that proves the 90 Rockwell rating by some organization other than Kahr. A 90 rating is almost as hard as I diamond and manmade processes that good I am skeptical of and require independent verification to believe it. Even the Kahrs with a black finish show holster wear. I have seen it firsthand.

I merely reprinted what kahr had written. I didn't write one word of that. Not sure verified their hardness either. I guess one could ask kahr and challenge them. Makes nadda difference to me. a good very hard and durable finish. I would say IMO any finish is WEARABLE to some extent. they do callit diamond like coating..



GET WELL MUGGYSY

[CJB]

I would like to see a link that proves the 90 Rockwell rating by some organization other than Kahr. A 90 rating is almost as hard as I diamond and manmade processes that good I am skeptical of and require independent verification to believe it. Even the Kahrs with a black finish show holster wear. I have seen it firsthand.

LZ, I respect you, but please don't shoot from the hip. Diamonds cannot be tested on any Rockwell scale of hardness. Rockwell scales A through... whatever... rely on indentation to determine hardness. They literally use diamonds as the intenter. Diamonds are measured on the Mohs scale, and they are a 10. Tungsten DLC... is supposed to be harder than 9 but less than 10. Non disintegrating "Grinding compound" is at or close to 9 on that scale, so Tungsten DLC is quite hard, but... also quite thin.

[getsome]

kahrs polygnoal barrels are made by Lothar. They come in 3 ft blanks and drilled and rifled when they get them, They cut the barrels into blanks and then the machine the chamber area and outside of the bbl. Then the barrel is sent off to a nickel plater. their regular barrels are made her in the Uj. S. buy a outside vendor and kahr does the above finishing work. Not sure of those barrels are forged or not. I am gonna guess even that the Lothar barrels which are German and with a stellar reputation of making great barrels, are probably not forged either.. Just sayin

The DLC finish on kahr slides is also a process that they do not put on their slides. It is an ouside vendor thing. It is rockwell hardness in the 60's that finish, so IMO its gonna takes some series holster usage to wear at the wear points even. U can google up kahrs DLC process and see how this is done even. Not just a spray and let dry finish, and I would be Glocks tennifer finish is very similar to. We are paying more for kahrs for some things that we take fore granite are of no expense to do..

Who are you and what have you done with Jocko????....Not one typo or misspelled word in that whole post....Sumpin wong

[b4uqzme]

Who are you and what have you done with Jocko????....Not one typo or misspelled word in that whole post....Sumpin wong

It appears good ol Jocko has learned to cut and paste but not to cite. ;)

Get well muggsy!

[CJB]

Maybe his lack of obfuscation is evidenced by recent alien abductions!

I pity the aliens.

[Barth]

I was pretty sure Jocko could misspell stuff even if is was a cut and past.
He'd just have to go in and fix it - LOL!

[Barth]

On a serious note.
I use ballistic nylon holsters and all my carry guns look NIB (Blue/Nickel/Stainless).
I've got stainless steel, stainless steel Isonite QPQ treated, blue steel Tenifer treated and even Fail Zero EXO Nickel Boron barrels.

Honestly, cleaned and oiled, I haven't noticed a difference.
Barth

[jocko]

ol jocko never misspells, its the fokkng keyboard. Just sayin




get well Muggsy

[muggsy]

Who are you and what have you done with Jocko????....Not one typo or misspelled word in that whole post....Sumpin wong

Cut and paste. :)