CPM 154 vs M4

Jun 23, 2010
I looked around on here and through google and could not find a good comparison between these two steels. It the future I will be having a custom knife built. The builder has given me a choice between these two steels. I am aware of some of the pros and cons, but I wanted to see what the overall opinion was before I make my decision.


It all comes down to what YOU want but I personally would go with M4 and depending on size I would adjust HT accordingly.
If you need stainless steel or if it would be highly desirable, go with CPM 154. If you don't, go with M4.
IMO, if it's any steel vs. CMP-M4, CHOOSE M4!

On a more subjective note, do you know how he heat treats the steels? Poorly or improperly heat treated steel can take away all of the qualities that made you want that steel in the first place. When buying from a custom maker, a review of that maker's (or heat treater's) steel is worth 100 reviews of that steel from another maker. I'm not saying the maker your going through doesn't do both steels perfectly, but the process to properly heat treat those steels is complex.
m4 may need a little oil on blade now & then but if heattreat is as good as the spydie mule in m4 i would rate it in top 5 of all cutters world wide. close to sniper blades 1095 by jody muller. dennis.
For a folder i would do the 154 since its stainless and you really wont need the extra strength that m4 offers. You wont have to worry about corrosion and it will still hold a very good edge. NoT to hate on m4(my favorite steel!) its just more of a fixed blade rough use steel. Unless you plan on doing some crazy stuff with your folder.
I am thinking that either way I really can not go wrong. This is a high end knife, and I was just trying to figure out what I will like better. I have always been a big fan of 1095 and all quality carbon steels. I know M4 is different, but I still like it. Just not sure how hard it is to keep up with.

Decisions, decisions.

I personaly prefer CPM154 because of the corrosion resistance. CPM154 is more than good enough in every area for my uses.
Either one will be a great choice. I haven't used CPM-154 but I have always like 154 cm for its ease of sharpening, corrosion resistance, good toughness, good edge retention and it will take a screaming edge. However M4 is great also. It is also pretty easy to sharpen and will quickly take a nicely polished hair poppin edge and its crazy tough. M4 doesn't rust easily IMO but it will take on a slight patina, more of just darkening up a bit in my experience. Ask the maker what hardness he heat treats both steels to. If he says the M4 is RC 63 or higher jump on the M4!!
Go with the M4. CPM-154 is common as dirt whereas M4 is still a rare bird, particularly in a folder.

Rarity aside, by all accounts it is great stuff and tough as nails!
Ask anyone with a Gayle Bradley what they think of CPM-M4. Great stuff. :thumbup::thumbup:
Could someone also explain to me the corrosion resistance vs. typical carbon steel. I have read it is better, but I do not quite understand what makes it that way. Also, other than either using it, or light oil on the blade, how hard is it to keep rust off it.


I have a couple knives in M4 and don't find it 'rusts' easy at all really. I think you would have to leave it laying in a sprinkler for a couple days to actually get red rust to show up. It will develop a patina or darkening of the steel when cutting some foods and maybe if put away a little wet. But I don't consider that rust. If you want to remove the patina all you have to do is put some metal polish on your finger (like Flitz or mag wheel polish) and rub the blade down for a minute. It will take the patina off in my experience and also makes the blade less likely of having a patina develop and it doesn't change the look of the original blade finish. I have lots of 154CM (not CPM154) and would choose M4 over it even though 154CM is great, M4 just seems a little better. M4 will take a screaming edge fairly easily in my experience and holds it pretty good.
Basicly i would go for M4, if it was not the first time, the knife maker makes a blade out of it.

First i would try to find out, what ppl. have reported about the knifemaker and the blades he has made with both steel grades.

Second, heat treatment, ask the way, he does and the achieved hardness and temperatures. If possible, it should be tougher and harder than CPM 154 or tougher as CPM 154 at same hardness or harder at same toughness.

Stain resistance is the least important, if not most unimportant property a knive could have, in my own personal experience. I don´t go diving or do any other kind of water sports. I have used a folder with a carbon blade over some time and never found a single spot of rust. Not on the blade, nor the tang. So you see, why i can let stain resistance aside.
Yeah - unless you absolutely need to have a stainless I say go with M4.

A good custom maker could probably eke more performance out of M4 - you'd probably be happier with how you spent your money.
what types of cutting are you planing to do and what kind of care are the biggest ? to ask yourself less you are buyin g a dress knife or safe queen