Home Forums Hunting & Shooting Ask The Gunwriters Barrel Steels: chrome moly vs chrome vanadium vs stainless.

So a question for the gun press members, and especially any gunsmiths, metalsmiths or metallurgists. Or just anyone with knowledge or experience.

What are the relative merits of these three types of barrel steels? What's the difference between chrome moly and chrome vanadium? Why would you choose one over another? How do either of them stack up against stainless for accuracy (which is very subjective no doubt), durability, ease with which to work on etc?

Chrome moly vs chrome vanadium is a wash.

The primary purpose of the chrome is to increase depth of heat treatment for a given severity of quench. The common grades of alloy steel have a skooch less than 1% chrome which is way more than is needed to ensure something as skinny as a rifle barrel achieves hardness to the core.

Moly in the amounts present provides a synergistic effect to the chrome, that is, deeper hardening or a less severe of a quench. The vanadium refines grain structure which has merit in springs and such. Neither are present in very large % (about a quarter percent). When present in massive amounts like 5% to 15% they provide fabulous wear and heat resistance due to massive, complex carbide formation. High speed tool steel is an example of very high moly and/or vanadium steels. But garden variety alloy steel has nowhere near enough to provide that benefit.

Stainless steel is corrosion resistant. It comes in many, many grades.

I have not worked with a chrome-vanadium barrel. Non stainless barrels have either been chromoly (4140 or 4150)or carbon manganese. Stainless barrels have always been 416 with the exception of some Lothar Walther barrels which are alledgedyly not 416 but I don't know what the composition is.
In general, 416 stainless is much easier to machine than is 4140 and macxhines more cleanly. Strangely enough, it is also harder on tooling than is the 4140 probably due to a slight tendency to work harden and due to being slightly abrasive in nature. Stainless is also a bit "sticky". GD

The way I understand it, stainless barrels were originally developed to increase erosion resistance in the barrel's throat. Stainless steel, with it's chrome content, is more corrosion and erosion resistant than chrome moly.

Stainless will erode, but it usually takes longer, and also a stainless barrel would better withstand heat from powder gases that would cause chrome moly to erode quicker.

To my knowledge, the only thing stainless had going for it is the increased erosion resistance and also the obvious advantages of rust resistant, although no steel in this class is completely rust resistant.

I have never read anything that said that a stainless barrel was, or could be, more accurate than a 4140 or 4150 barrel. Only that it was more resistant to wear and erosion in the throat area, and the obvious resistance from oxidation.

The above is not proven fact. It is my opinion based on studying the properties of stainless steel, as applied to cutlery, containers made for acids and other corrosive material, and, in some instances, more resistant to corrosion and erosion at elevated temperatures.

My experience is that stainless, even in the annealed condition, is more difficult to machine than carbon steel. It does have a stick feel, and it will work harden if you are not careful.

This is another of my opinions, but I think that a chrome moly barrel would be easier to machine than a stainless barrel, and it would be easier to drill the chrome moly barrel straight, and to get a more uniform and better finished bore.

Frank Green of Bartlein Barrels uses CM barrels for competition and said it makes no difference for an accurate barrel. The CM could corrode a little easier if not treated properly. LW uses a proprietary steel that they call LW50. I believe it is maybe like 17-4 stainless. It does need to be machined with different methods than 416R. It is tough to machine. It takes much more lathe speed and feed. It will probably make a long lasting barell, but haven't seen any on a competition rifle since the mid 90s when they tried with Blackstar.

When I asked a well known barrel maker why they only offered light contours in CM, they replied that SS does not have the fatigue resistance that chrome moly does, therefore it has to be made up in wall thickness.

I'm not sure what to make of that, given so many barrel makers offer lightweight SS barrels.

bobnob17,

I'm not a barrelmaker, gunsmith or metallugist, but have visited with a lot of barrelmakers and done some reading, especially military research about barrel life. They do a lot of research, due to using so many automatic weapons.

From what I understand there's no real difference in barrel life between stainless and non-stainless steels--though a lot of shooters do apparently confuse the corrosion resistance of stainless with erosion resistance, a completely different thing.

The big advantage of stainless is corrosion resistance, but the stainless steels used for barrels don't contain nearly as much chromium as other kinds of steels, so are subject to rust, especially in extreme conditions (coastal air) or when in contact with non-stainless steels. Stainless is also apparently not quite as pressure-resistant in very cold temperatures, but it has to be pretty damn cold to encounter problems. I've never had any in decades of hunting in Montana when shooting at zero F. or even colder.

A lot of target shooters use stainless barrels because then they don't have to worry so much about bore corrosion when shooting in different atmospheric conditions, plus there's no need to pay to have the barrels blued, a needless expense when changing barrels more often than most shooters.

Mule Deer:

I can remember when Winchester first came out with the M70 in .264. It had a stainless barrel which was iron plated so that it could be blued. This might or might not have been the first stainless barrel, or the first factory rifle with a stainless barrel.

It has been a long time ago, but seems like I remember reading that the reason for the stainless barrel was for better heat and erosion resistance because of the large amount of powder in such a small bore size. To the best of my knowledge, heat has an effect on throat erosion, and the small bore size and large powder capacity caused the .264 to produce more heat than cartridges of similar capacity but larger bore sizes. That, and hopefully longer barrel life was the reason for the stainless barrel.

This might not be factual, but it seems to be what I remember from a long time ago.

Everything else being equal, stainless would have better corrosion resistance in a hostel environment (wet and salty conditions) than would a chrome moly barrel but the actual purpose, at the time, was for better heat and erosion resistance.

1234567,

Actually, I believe the M70 .264 Westerners had chrome-moly barrels. I know for sure the one I owned did.

Remington used stainless barrels on the first 7mm Magnum 700's to reduce erosion, but lots of research since had proven stainless doesn't resist heat erosion (the root cause of throat burn-out) any better than chrome-moly.

1234567:

I believe that Harvey Donaldson, in one of his columns for the old Rifle Magazine, wrote that Winchester's first use of stainless steel barrels was on their pre-WW II .220 Swift rifles. If I remember correctly, Donaldson wrote that he still possessed such a rifle, a Model 70, and that it still shot well enough to use as a varmint rifle despite the original barrel's 3000 or more rounds. Donaldson said the secret was to allow plenty of time for the barrel to cool between shots and to clean the barrel meticulously after every outing. That column may have been reprinted in the Wolfe Publishing book, "Yours Truly, Harvey Donaldson." Anyone who has the CD version of the older issues of Rifle Magazine can probably check my allegations in a short time.

First and foremost chrome moly and stainless are barrel steel's......chrome vanadium is used in the wrench to tighten them to the action but not a barrel steel

Actually, I saw a Model 54 Winchester carbine in 30/06 which had an original stainless steel barrel (20"). I was quite startled to see this because I really didn't think such an animal existed.
Looking at barrels with the bore scope, it looks to me as if the stainless may erode as much but it erodes differently. I don't see the surface cracking in the stainless to the extent that I do in chromoly. GD

I had one of the Remington 7mm mags with the stainless steel barrel, it had the iron coating and was blued. When every was into the down with white line spacers I sold it, big mistake, it was a wonderful rifle great groups classic style I miss it.

Thanks mate. This is one of the reasons I asked. I own a Zastava M70 in 270. The brochure that came from the Serbian factory with it says the barrel is made of chrome vanadium steel. This is paraphrased on the Beretta Australia web site...

"Sporting rifles Zastava M70 are famous for their authentic Mauser locking system (rotating bolt). Barrels are made of cold forged chrome-vanadium steel, which enables constant accuracy and exceptional durability."

Here is the link, hope it works...

http://www.berettaaustralia.com.au/zastava-arms/zastava-lk-m70-synthetic-stock.html

So this is what I am on about. Is it a cheaper inferior product, or a good one?

No mind, I am happy with the performance of what was a cheap and seemingly very rugged rifle. It shoots 'em straight.

Thanks for the really interesting info though. I am not much of a scientist or techie so it was a great read.

- Bob

Bob,I am not seeing where it tells the barrels compostion!!!!Huntz

Scroll down the page and read the description beside each model

I've never read any documented evidence of the merits of one steel over the other....Chrome-moly verses stainless....in regard to barrel life or accuracy.

The stainless is not real stainless as it will discolor to a degree.

As far as I'm concerned the biggest difference is that in the end one should pay for bluing on the chrome moly and may omit that step with stainless.....to me this makes stainless a bit less costly.

Huntz, under "Description" which is under the picture of the rifle, ie:
Sporting rifles Zastava M70 are famous for their authentic Mauser locking system (rotating bolt). Barrels are made of cold forged chrome-vanadium steel, which enables constant accuracy and exceptional durability. Metal parts have surface protection and the rifle features black synthetic stock. These sporting rifles are produced without mechanical sights and it's possible to mount optical devices.

Since earlier today, I have been searching the net about Chrome-Vanadium steel, and it seems there is very little information available, or else the companies using it are keeping quite about it.

I cannot find the composition of any chrome-Vanadium steel that might be used in gun barrels.

The information I have been available to find applies mostly to rapid firing guns, such as the M4 and AR15, and full auto machine guns, and the claim is that the chrome vanadium barrels will give longer barrel life because the vanadium makes the steel more heat resistant. But, this longer life only applies to rapid fire firearms, where sustained firing would cause the barrel to become very hot.

The closest thing I can find to a chrome-vanadium steel that would be used in gun barrels is one named 41V50, and is about the same as 4150, but with about 1% vanadium added.

From what little I can find, it seems like the only advantage of having a chrome vanadium steel barrel is in a machine gun, and none of the information I can find goes into detail about how much of an advantage this is.

Notice I said "all of the information I can find..." does not mean that the information is not there, only that I haven't found it.

Mule deer:

As I said, I and trying to recall what I said about the .264 from sometime pre 64. I thought I remembered reading that the .264 had an iron plated stainless barrel, for the reasons stated. You said you had a CM .264 barrel, so Win. must have used two different types, or more, steel on their .264.

If both Win. and Rem. used stainless steel, iron plated so that it could be blued, I fail the see why unless the engineers at the time felt there was some advantage to stainless steel. Otherwise, I can't see the point in going to all the trouble to make a stainless barrel and plating it so it could be blued.

And I don't think this advantage, if there was one, would be corrosion and/or rust resistant, because the iron plating would rust.

MIL SPEC MIL-B-11595, or "0RD4150 Chrome-Moly-Vanadium", Bar, Metal and Blanks, Steel (Under 2 Inches in Diameter) for Barrels of Small Arms Weapons, is basically 4150 with .2-.3 V...

1234567,

Thanks for that info. All I could add to that would be that I know Zastava - who made my rifle - do in fact make all sorts of stuff including heavy and light machine guns. Just a stab in the dark but maybe they make their bolt action rifle barrels from the same barrel steel rather than having different steels for smaller volume runs.

In fact on closer examination the Zastava company is an interesting one. They make all kinds of weird and wonderful crap!

Gotta love them eastern Europeans!

- Bob

Thanks too Journeyman. Starting to make a little sense.

I will get back to you guys in about another 5000 rounds and let you know how this rock-hard vanadium barrel is holding up! Should only take 10 or 15 years...

Bob,thanks I found it now.You learn something new every day.

Yeah we do learn something every day... now at least I know what vanadium is. I suspect as this is a cheap rifle - but all things considered a pretty good one - that the vanadium steel is not necessarily any better. Probably cheaper than the chrome moly used in most more expensive rifles.

Anyway it shoots well now, and only time will tell about the durability of it.

"Probably cheaper than the chrome moly used in most more expensive rifles."

I wouldn't think it would be cheaper. From what I have been able to find, the chemical composition of the chrome moly and chrome vanadium is about the same. The difference is that the chrome
moly has vanadium added to it.

It still has about the same amount of moly, just vanadium added. I would not think this would make it cheaper. I don't think either one is any better or worse than the other, other than the chrome vanadium has more heat resistance, so it might give better barrel life especially in rapid firing guns.

I don't see why one is chrome moly and the other is chrome vanadium. Chrome moly has moly and chrome vanadium has both moly and vanadium. Looks like the one with vanadium added could be named chrome moly-vanadium. The latter would be a better description of what the steel actually is.

Is "stainless" not "stain proof"

SS barrels will stain and corrode.

I thought that was well established

When comparing steels used for gun barrels and knives, or, for that matter, any stainless steel that can be heat treated, are actually somewhat rust resistant.

By this I mean, Stainless barrels and knives will rust, but they are more rust resistant than non stainless. That is because so called stainless, as used in firearms and knives contain from about 14 to 17 percent chrome.

Stainless used for structural purposes and kitchen ware contain upwards of approximately 19-20 percent chrome.