CPM440V or ATS34

Jul 4, 1999
Well, I'm going to get a Spyderco Military, but should I get the CPM440V or the ATS34 version?

Is the 440V really worth the (considerable) extra cost?

Remember--pointy end AWAY from you!

John 14:6

When I read the long diatribes on knife steel, I begin to think there is as much fashion in the knife industry as in the apparel industry.

If you've tested a 400mhz computer along side a 450mhz computer, you'd see that the differences between them are measurable but not noticeable to the user. The same can be said about most of the "fashion" steels. Don't mistake me, I'm not suggesting they aren't good. I'm suggesting the differences between them are measurable and not noticeable. They will all perform well in a knife. So will most of the "unfashionable" steels. It's not a very big deal.

Knife Outlet

Fred, if the differences are not meaningful to you that does not mean they are not meaningful to everyone. In reference to your computing power statement for example, the numeric problems we currently have to solve are very complex. On a low level Pentium (a couple of years ago), it used to take three days to get the results for one point and we had to take about 10 point a set, and 3 sets per experiment. Everytime we got an upgrade I could see the difference and see it strongly. No you don't need a 450 Mhz to read email but there are lots of people who need it and more besides.

It is the same thing with knives. There are differences between knife steels and the difference are immediate and obvious as soon as your uses pass the stress levels of the weaker steel. If your use is below both steels then obviously either will be adequate so just go with the cheaper one. But the difference is there. For example, I recently compared Busse's INFI and 1095 (an Ontario machete). I recorded the numer of slices each took to cut through a roll of fabric, chopped 300 times into a piece of spruce and then repeated the fabric cutting. The 1095 blade had degraded to well over twice the number of strokes required, the INFI was not effected.

In regards to Spyderco's 440V and ATS-34, make a post in their forum. What I would say, while not having any direct personal use, is that Spyderco tends to look at steel upgrades rather seriously, I would not take their decisions lightly.

Additionally, there were other improvements made to the knife design along with the new steel according to Sal and the Spyderco people. The new Military (440V) is indeed a fantastic knife.

My .02,

I wouldn't buy a knife with ATS-34, except as a novelty. This is a function of my personal way of using and maintaining knives. I prize a knife alloy for the absolute sharpness that I can achieve with the blade and how hard it is too keep the blade ultra-razor sharp. ATS-34 has a lot of molybdenum in it which makes it resist wear, but makes it a relative pain to sharpen to my edge standards. CPM-440V is also a pain to sharpen, but it is ultra-high in vanadium, which refines the grain structure of the alloy and lets you get an ultra sharp edge for your trouble.

I think that it is great that you can get CPM-440V in a 'production' knife. My hat is off to Sal and Spyderco for making it available. On the other hand I would be confident that Spyderco would do a good heat treat on an ATS-34 blade that would produce very good value for most users.
The actual heat treat and blade design makes for more of a difference but it seems that 440V is one of the steels more brittle than ATS-34, which already seems to have a reputation for being brittle.
There is a difference. Plus I prefer a steel that was primerily design as a knife steel (CPM440V). Not a turboprop steel that happens to have good blade steel characteristics (ATS34).

Plus I have had very good experience's with CPM steels (420 actually not 440) and bad experiences with ATS34. That's not to say ATS34 is bad, I have knives made of this and they're fine knives.

In the end though it's like a previous poster said, if you need every little bit of capability in a knife go for the 440 if not and cost is your biggest issue get the ATS34

~ JerryO ~
Based on lots of expierence with a pair of military's one in ats and one in 440v I have to say there is no comparison. By far the 440v blade is the best way to go if you are looking for the best edge holder.


Tom Carey
Cliff Stamp, Jeff Clark and Tom Carey all make excellent points.
440V and ATS 34, when the heat treat is done right, as Spyderco does, make great knife steels.
It is my experience, however, that 440V holds a better edge than ATS 34.
This is not to take away from ATS 34, it too holds a fine edge, just not with the tenacity that 440V seems to have.
Of course, this is all IMHO.
I've got the 440V Military and the Starmate and I wouldn't trade them for anything. Ever. they are that good.

If it's stupid but works, then it isn't stupid.

About the only unequivocal thing I can say is that the 440V blade will take a finer edge.

On paper, the 440V blade should hold an edge longer, assuming that you would sharpen either steel the same way. You would probably have to want to field dress three elk without sharpening instead of two to appreciate the difference in the real world. We should all be so lucky.

I don't have any experience with S-co ATS-34, but niether steel is known for toughness when bulk heat treated, and I would predict a draw.

440V is not really any harder to sharpen than any other steel as long as it doesn't get too dull. Changing the edge shape is a lot of work, but just restoring the edge to perfection after ordinary light use is no harder than on anything else in my opinion, so as long as you sharpen just as often.

Go for the 440V blade. It takes a really impressive edge, and the intangibles of having a high-tech steel knife blade count for something too.

Or, you could get the M-2 AFCK. Then you would have the edge holding of the 440V, plus better toughness, and a stronger handle.
(Doh! Loose the hounds!)


My ATS 34 experience lies strictly with
factory blades.The 440V blade in my Military
is lightyears ahead in edge holding and ease of sharpening .I am absolutely right in what
I say based on the knives I own.Someone else
can have the same brand and model knives as I , have a different opinion , and be right also . ATS 34 is sensitive to heat treatment variations and quality varies from batch to batch and I will bet , even within a batch .Im my opinion , ATS 34 is a crap shoot and 440V is a sure thing.
The Military in 440V is an awesome knife. The edge holding is among the best that I have seen for production folders.
Between the edge holding of 440V and ATS-34, I would have to say go with the one with the better edge geometry and heat treat.
The only experience I have with 440V is with my BF Native, and it doesn't hold its edge as well as the ATS-34 of my BM 710 Axis. I believe that's because it has a thinner edge, and softer heat treat. Oh, waitaminit, you said Military in ATS34 or 440V. Oh, well, hmmm... I'd probably say go with 440V based on what others say.

Work hard, play hard, live long.