Benchmade M2?

Mr. Dave

Mar 10, 2000
Does BM's M2 really take and hold an edge that blows aways their ATS-34 like some of the promo lit suggests? I've got one of their ATS-34 knives and that stuff is pretty darn hard.

M2 is a tool steel, which means it is intended to cut other steel. It will take and hold a better edge than ATS-34, but it is not a stainless steel (ATS-34 is), so it will rust easier. In some situations, this is unacceptable, so better edge holding is of less importance. I don't know exactly how much better the edge-holding needs to be for you to say that is "blows away" ATS-34, since that is a personal feeling.

Incidentally, A2 is supposed to be the same as M2, but with less high-temperature resistance (which isn't needed in knives, but is in lathe tools, etc.). Can one of our resident experts chime in as to whether I have that correct?


I may not be an expert on the topic, but as far as I know and have been told by Machinists that actually work with this stuff, ATS-34 is also a tool steel...
I do not know the difference between the two steels, but apparently, M2 has significantly better edge holding characteristics, than ATS-34...Haven't tried it yet myself though...Sigh, maybe I will just have to get myself a Nimravus in M2....Arrgh, more knives to buy...

Joshua "Kage" Calvert

"Move like Water, strike like Thunder..."
I'm not a metal technology expert but I think that generally you are correct.
One advantage of high-speed tool steel you are missed could be higher impact resistance. It can be essential for your knife or not - depending on intended knife use.
M-2 is a steel designed for superior edge holding at temperature of 1000°C (sorry, the rest of the world uses the metric system). It is mainly used in drills (marked HSS high speed steel). M-2 isn't excactly HSS, HSS is a little lower alloy, but the characteristics are the same.The better edgeholding comes from the fact that M-2 can be hardened way beyond 60 (like ATS-34)and still not be brittle. A-2 is not the same steel. It is totally different. A-2 is for those who require extreme toughness and pretty good edgeholding, but don't care for rust. A-2 rusts faster than M-2, because M-2 is a higher alloy, with more chronium. My preference for a knife-steel would be 52100, differentially tempered. Better edgeholding, a lot tougher and rusts the same. I think all stainless steels are only good when rust prevention is a factor. And I don't care for a little dark spot on my blade.
B.T.W. ATS-34 rusts too, just not so fast. Just take it out camping and cut jour steak with it, and let it lie there till the morning. It will be stained, about as much as the same threated M-2 blade.

Hope this helps.
I am a fan of Benchmade's M-2 blades, but the reason is toughness, not edge holding. I have compared a M-2 AFCK, ATS-34 AFCK, and a CPM440V Spyderco Military, side by side for edge holding, and did not detect a meaningful real-world difference between them. Big difference in toughness though.
I think the M2 steel is fantastic. It does indeed seem tough and IMO holds an edge markedly better than Benchmades ATS-34. I have carved maple to the point of blisters on my hand, cut through numerous sandwiches and the plastic on my tailgate bed liner with my M2 nimravus and it still shaves hair. I have never had this good of edge holding with any of my other knives before. I stripped the coating on mine and have had no problems with rust either.
For what it's worth:

The other day I was cutting up some chicken wire. I was using the wire cutters on my Leatherman Supertool, and just for the heck of it I decided to see how much trouble it would be to use a knife blade instead. I tried cutting the wire with an M2 AFCK, a serrated Endura, and a Sebenza. All three blades suffered damage. In the case of the Sebenza the damage was in the form of a semicircular chip, less than one mm, but easily visible without magnification. In the case of the M2 AFCK, the damage was due to deformation rather than breakage, and the edge could be restored fairly easily with a few strokes on the Sharpmaker. The damage to the Endura's edge seemed to fall somewhere between the other two: edge deformation with a bit of what looks like minor chipping.

All three of these blades had been sharpened to a high performance (i.e., as thin as I could conveniently get it) edge. I blame the damage in all cases more on the accuteness of the edge angle than on the steel.

The bottom line is that the M2, even with a very accute edge, was highly resistant to major damage. This toughness enables a person to sharpen the knife for high performance cutting with less fear of significant edge damage. In the future I will consider sharpening the Sebenza and the Endura to 40 degrees rather than 30 or less degrees as I had been doing.

How does the story end?

After mungering up the high performance edge on three good knives, I finished the job with the Leatherman.

David Rock

AKTI Member # A000846
Stop when you get to bone.