There are high end steels for knives, and then you have the premium steels. But at the highest tier you find the ultra-premium steels, which are widely regarded as the best of them all for knives. And among these steels stand the relatively new M390 steel from what’s now known as Bohler-Uddeholm. This is a super-steel that’s worth the expense, since you get all its benefits for basically the rest of your life.
With this guide, you get a closer look at that makes the M390 steel so special, and why it’s a super-steel for knives. It examines its chemical composition, and gives you an idea of how it performs compared to other similar steels.
Finally, you get a list of terrific knives that use the M390 steel for the blade. The good news is that none of them cost more than $200, and most of them cost less than a hundred bucks.
What is M390 steel?
The M390 steel comes from Bohler, and the manufacturer actually applied for its patent way back in 1989. It’s widely known these days as a super-steel, and today it’s very popular for knives.
Ironically, its use for knives was almost an afterthought. Even now, Bohler insists that the M390 steel’s main use is for molds for the injecting molding industry. But plenty of brands now feature this steel for their premium knives, and they’ve all proven to be quite popular.
The M390 steel actually came before the arrival of other super steels like Elmax, ZDP-189, and CPM S90V. but those other steels were used for knives before there were knives made with M390 steel. Other companies made versions of M390 steel first, before Bohler also made their steel available to knife manufacturers.
Why is Böhler M390 So Popular?
As it turned out, the qualities that made the M390 steel suitable for molds are also the same qualities that made it ideal for premium knives. This is mainly its extreme resistance to wear and tear. Buy one today, and 10 years from now the steel will be just as good.
With M390 for the knife blade, this means that your knife will have fantastic edge retention. It’s so resistant to wear and tear that it can keep the shape of the edge for a very long time.
As you know (or should know), edge retention plays a very large part in the overall durability of the knife. The more often you sharpen your blade, the faster it will eventually wear out.
Add the fact it’s reasonably tough (given its hardness) and that it’s also resistant to rust and other corrosive materials, then it’s easier to understand why some people simply regard it as almost perfect.
Common Uses of M390 steel
You’ll find the M390 steel used for the following:
- Molds for the injection molding industry
- Ball bearings, screws, barrels, and other parts found in jet engines
- Smaller fixed knives (especially for outdoor activities)
- Flip knives and other small knives
- Knives for display and decoration
M390 Steel Chemical Composition
The chemical composition of any steel is like its DNA—you can tell a lot of their characteristics from the elements present and how much you get of each element. (If you push the analogy farther, then the heat treatment of the steel is the “nurture” part. How the steel is prepared also determines how the steel will perform).
- Carbon, 1.9%
- Manganese, 0.3%
- Silicon, 0.7%
- Chromium, 20%
- Vanadium, 4%
- Tungsten, 0.6%
- Molybdenum, 1%
In any case, here’s a list of the elements present along with their percentage levels within the alloy.
Carbon, 1.9%: Carbon is the most important element present in any steel, as it’s the main determining factor for the steel’s hardness and performance.
And here, you get a lot of carbon. Quite a few “hard steels” contain only 0.5% carbon, and they’re already very hard. Some carbon steels have 1% carbon and they’re among the most popular due to their performance levels. Now, with 1.9% carbon, you don’t have to worry about insufficient hardness.
Manganese, 0.3%: This is the 2nd most important element next to carbon, with similar properties to carbon as well. It takes out unwanted sulfur and oxygen, improves machinability, and boosts tensile strength and hardenability.
Silicon, 0.7%: This also removes oxygen bubbles from the molten steel. In small amounts, it helps with hardness and strength. But too much can lead to lower ductility.
Chromium, 20%: When you realize that stainless steel requires at least 10% to 12% chromium, then you’ll realize that this is the main reason for the good corrosion resistance for M390. It also boosts hardenability and yield strength.
Vanadium, 4%: This is a necessary component because powdered steel depends on the proper distribution of fine grain, and vanadium produces fine-grained steel during the heat treatment. It also boosts shock loading resistance, fracture toughness, and hardenability.
Tungsten, 0.6%: The main problem with having too much chromium (and other elements like carbon that increase the hardness) is that the toughness level of the steel drops as a result. But the tungsten compensates for that issue.
Molybdenum, 1%: It acts similar to manganese and vanadium, boosting temperature strength and hardenability. It also increases creep strength and resistance to corrosion.
M390 Steel Hardness
Among the stainless-steel knives, the M390 steel is one of the hardest. It’s able to achieve a Rockwell hardness rating of 60 to 62 HRC. That makes it terrific when it comes to edge retention and resistance to wear and tear.
Properties of M390 steel
Here are the features you can expect from M390 Steel:
Fantastic Edge Retention
This is perhaps its most notable benefit. Its hardness offers fantastic slicing and cutting performance, but you won’t have to sharpen it too frequently.
Terrific Resistance to Wear and Tear
Because you don’t have to have to sharpen it often, it will most likely last you for a very long time. That’s good, because M390 can be very expensive. You can at least calculate its cost per year, and you’re actually paying a very low price compared to the performance you’re getting. The M390 can last you for decades, if not for the rest of your life.
Good Corrosion Resistance
This is another reason why it lasts longer, and why you can use this for camping and hunting. The corrosion resistance is terrific thanks to the high chromium level. You can use this in wet conditions every day and it’ll remain spotless.
Just don’t use it every day in saltwater, as that’s not its forte.
Better than Expected Toughness (Relative to Its Hardness)
True, it’s not very tough. You don’t want this steel for your sword or axe. It’s even risky to use this to pry cans open.
But it’s still tougher than many other hard steels out there. That’s why some M390 steel knives are remarkably thinner than usual.
Easier to Sharpen Than Most Super Steels
Admittedly, it’s much harder to sharpen than most steels out there. A basic Arkansas stone just won’t do. But a lot of the other super-steels are more difficult (and more frustrating) to sharpen. But you can use a diamond-coated stone with a fixed angle, and a bit of patience, and soon enough you’re done.
Can Achieve a Mirror Polish
Look for this feature if you like to show off your M390 steel knife for decoration.
But to be honest, that’s just a waste of terrific steel. The M390 steel is meant to be used for heavy slicing duty, and it won’t fail you. Use this for slicing packages open every day, and it’ll take months before you need to sharpen the blade. You can use this for camping too.
M390 Equivalent Steels or Alternative
Let’s check out how the M390 steel compares to other premium steels that are popular due to their super performance.
M390 STEEL vs S30V
This may not seem like a fair matchup, since the s30v steel is at a lower premium tier. The M390 is part of the ultra-premium level, which is the highest tier of knife steels in the industry.
The M390 outscores the S30V steel by 9 to 7 (out of 10) when it comes to edge retention. They score about the same (7 for both) for corrosion resistance, though technically the M390 steel is also a bit better.
However, the M390 is a bit more difficult to sharpen, scoring just 2 out of 10 in this area. The relatively softer S30V steel is much easier to sharpen, scoring 5 out of 10.
M390 Steel vs Elmax
Who comes out ahead of this matchup between 2 super-steels? It’s like Godzilla vs. King Kong all over again.
The M390 steel does come out ahead of Elmax steel for edge retention, scoring 9 against 8. The M390 also does better in resisting corrosion, scoring 7 against the 5 for Elmax.
However, the Elmax is famous for being the easiest to sharpen among all the super steels. It scores 3, against the 2 out of 10 score by the M390 steel.
M390 Steel vs CPM 3V
This is like comparing opposites, even though the CPM 3V can achieve a hardness level of up to 60 HRC. That means the M390 does better when it comes to edge retention and wear and tear resistance.
The CPM 3V is also not stainless steel, and the M390 is. So, the M390 is better at corrosion resistance.
But the CPM 3V is famous for its terrific toughness. That means the CPM 3V is better for longer knives used for grueling outdoor activities.
M390 Steel vs N680
The N680 is considered the brother of M390 steel, as both come from Bohler. But for edge retention, the N680 is the little brother. It scores just 5 compared to the 9 that the M390 scores for edge retention.
On the other hand, the N680 is a bit more corrosion-resistant (scoring 8 against the 7 for M390). This is surprising, since the N680 has only 17% chromium while the M390 has 20% chromium. Also, the relative softness of the N680 makes it much easier to sharpen (6 vs. 2).
Is M390 Steel Good for Knives?
Yes. That’s the short answer. Plenty of people already know this, which is why it has been extremely popular for knives for the last few years.
It is extremely great at holding its sharp edge, even if you use it daily. It will take a long time before you need to sharpen it. Then you add its excellent corrosion resistance, and you’ve got yourself a winner.
It’s true that it’s relatively hard to sharpen, but some of the super steels are even harder. It’s also not very tough, but relatively to its hardness it’s tougher than you’d expect. Finally, this can be polished to get to a “true mirror” level.
Pros & Cons of M390 steel
What are the benefits and drawbacks of using M390 steel for knives?
Best M390 steel Knives
Here’s a nice list of the top M390 steel knives you should consider. They all have reasonable prices, with none breaching the $200 mark. Most don’t even cost more than $100.
#1: LionSTEEL M4 Bushcraft Fixed Blade Knife
- Overall length: 204 mm
- Blade length: 95 mm
- Blade thickness: 40mm
- Handle thickness: 21mm
- Blade material: Bohler M390
- Blade finish: Satin
- Handle Material: Santos Wood
- Weight: 146g
The knife measures 7 inches long, with the drop-point blade with the hollow grind edge accounting for 3.74 of those inches. It’s a fixed blade that works for EDC and for various outdoor activities. The M390 steel is tough enough that this works with a blade thickness of 0.159 inches.
The blade profile is meant for general usage, with its spine rounded enough to work for skinning. That spine also has an edge you can use with firesteel. Out of the box, it’s sharp enough to shave.
It’s easy enough to carry this around, with its sheath made with double-stitched leather with a snap enclosure. It’s high quality. The handle comes with lanyard hole as well.
As for the handle, you have 5 options to pick from. We went with the reliable G10, but there are micarta options plus Santos, Olive, and Walnut woods.
#2: Off-Grid Knives Elite Series knife
- Weight: 4.58 (oz.)
- Blade Length: 2.78 (in.)
- Blade Length: 2.78 (in.)
- Blade Width: 0.95(in.)
- Blade Thickness: 0.15748 (in.)
- Blade Hardness: 59 (HRC)
- Blade Material: M390
- Handle Length: 4 (in.)
This is also known as the Black Mamba, and a lot of people are surprised it doesn’t cost $500. Yes, it’s that good. It’s a favorite among quite a few members of the law enforcement community. It has a reverse tanto design with the length short enough for legal carry in most places. The overall length is 6.78 inches with the handle measuring 4 inches.
They’ve coated the M390 steel with DLC (diamond-like coating) to boost the strength and corrosion resistance even more. Then you have Grade 5 6AL4V titanium with the hexagon pattern scales for an even better grip. The titanium is strong yet not too heavy, and it’s also great at resisting corrosion.
This comes with a deep carry pocket clip for EDC discretion, and when you take it out, its all-black look minimizes reflections. Of course, the all-black look for both the blade and the handle does make the knife look really cool, and that’s always a good thing.
You carry this with the tip up for quick deployment. The flipper tab features aggressive jimping to let you get the blade out surely and quickly. It also helps that the ceramic bearings allow for a smooth flip of the blade.
This is meant to last a lifetime, with the durability of both the M390 steel and the titanium handle. Get one, and you won’t need a replacement for decades.
#3: Kershaw KS1776BLK-BRK Link Linerlock A/O
- Blade Length: 3.25 in. (8.4 cm)
- Blade Material: 420HC
- Blade Thickness: 0.11 in.
- Overall Length: 7.6 in. (19.3 cm)
- Weight: 4.8 oz. (136.1 g)
- Blade Shape: Clip Point
- Country of origin: USA
Here the blade measures 3.25 inches, with the overall length when open at 7.6 inches. When closed, it’s more compact at 4.4 inches.
This isn’t hefty, but it has a nice solid heft to it. It features aluminum scales with the steel liner. The blade is nicely centered and everything’s a bit tight at first.
But its assisted opening mechanism loosens up the flipping process after a week of constant use. It even has a nice sound to it when it flips open. It comes out very sharp, and it looks great with the stonewashed finish. The handle also comes with a lanyard hole, but you also get a pocket clip for easy carry.
#4: Samior GP035 EDC Folding Pocket Flipper Knife
- Blade Length: 3.5″ (89 mm)
- Closed Length: 4″ (102 mm)
- Overall Length: 7.87″ (200 mm)
- Weight: 1 oz
- Blade Material: Bohler M390
- Handle Material: Carbon Fiber
- Pocket Clip: Tip-Up Right Carry
- Blade Edge: Flat
Now this is a very slim knife, and Samior rightly categorizes the GP035 model as its small slim EDC folding knife. It’s like a pen you can carry around, ticked in your shirt pocket or jeans.
With its full flat grind, it’s great for daily slicing use in the workplace when you constantly open packages and cut ropes or tape. In fact, you can even use this as your backup knife for cutting steak. The whole blade is only 4.3 inches ling when closed, but the blade itself is 3.5 inches long.
Opening this is simple enough, with the flipper tab and the ball-bearing pivot system for a smooth open. The handle is made with lightweight titanium, which offers a smooth and secure grip. There’s no texturing, but then you don’t really need it for EDC.
#5: Spyderco SpyOpera Folding Knife
- Overall Length: 6.90″ (175mm)
- Blade Length: 2.90″ (74mm)
- Steel: M390
- Closed Length: 4.03″ (102mm)
- Edge Length: 2.72″ (69mm)
- Weight: 2.7oz (77g)
- Blade Thickness: 0.118″ (3.0mm)
This is the most expensive of the bunch, but the price is still reasonable. After all, you’ll find other M390 steel knives that cost twice as much as this one, and they’re not twice as good. In fact, you might even prefer this model regardless of the price.
This is meant for utility, with the Round Hole to make it much easier to open. It’s 6.9 inches long when open, with the blade measuring 2.9 inches. That makes it legal to carry in more places. Even you won’t notice it, since it only weighs 2.68 ounces.
The micarta handle has scales for a better grip, along with the skeletonized full titanium liners and the stainless steel backspacer. The craftmanship is impeccable, and you get a deep-pocket wire clip for tip-up carry on your right.
It seems quite obvious that M390 steel for your knife is, in a word, fantastic. It’s no wonder it’s so popular. Perhaps the costs of these knives may deter some from buying it, especially those who only use their knives every so often. But our list of top M390 steel knives come in more reasonable prices, and offer terrific value for money.
Get a good M390 steel knife for your EDC and outdoor adventures, and you’ll have a useful companion for years to come!
Frequently Asked Questions
Does M390 Steel Rust?
Yes. While it’s true that the M390 is a stainless steel, that doesn’t mean it will never rust. This is especially true if you use the M390 knife regularly in saltwater.
However, it is also true that the M390 does very well when it comes to resisting rust. You won’t find spotting on your blade if you use your knife in wet conditions, especially if you take care to wipe it down afterwards.
Is M390 hard to sharpen?
That depends on what you mean by “hard to sharpen”. If you’re going to use a basic Arkansas stone, then you’re going to have a hard time. You will need stones and ceramic options, coated with diamonds. Then you have to set up your sharpening system for a very fixed angle.
At least you’re not dealing with the CPM S90V or the CPM S110V. Those are just frustrating to sharpen!
How to tell if the knife really uses M390 steel
Well, you can’t unless you have the specialized equipment to actually check its chemical composition.
But you can do your research on the knife brand, and confirm that they do use the M390 steel from Bohler. You can even find online lists of all the fixed knives and pocket knives made with M390 steel.