• The BladeForums.com 2024 Traditional Knife is ready to order! See this thread for details: https://www.bladeforums.com/threads/bladeforums-2024-traditional-knife.2003187/
    Price is $300 $250 ea (shipped within CONUS). If you live outside the US, I will contact you after your order for extra shipping charges.
    Order here: https://www.bladeforums.com/help/2024-traditional/ - Order as many as you like, we have plenty.

  • Today marks the 24th anniversary of 9/11. I pray that this nation does not forget the loss of lives from this horrible event. Yesterday conservative commentator Charlie Kirk was murdered, and I worry about what is to come. Please love one another and your family in these trying times - Spark

Any makers working with CPM M4?

I sharpened a Spyderco Mule Team in M4 a few weeks ago and it is one of the sharpest edges I have ever put on a knife. I would love to see more people use this steel.
 
I have seen alot of talk about M4 originated by people who have the Mule. Wish I would have bought one so I could compare apples to apples with you guys. The only M4 i have used is ones I have made and the other cutting competition knives I'm around. I plan on getting the Gayle Bradley Spyderco with M4 blade so that should help.
 
I've been using my Mule M4 (awesome job by "defaultuser" on the handles and sheath) since I got it, I still find it as sharp as when I first got it!
 
What's the optimal hardness range of M4? Most people seem to be running them 61-63 hrc. My M2 is just fine at 63-64 and M4 is tougher than M2, so wouldn't ~64 be ideal for M4 (and ~62 for larger knives)?
 
My competition knives punch at 61 Rc and my work knife with a 4" blade punched at 63.5 Rc. I have not had any problems with the 4" blade chipping or anything.
 
the possum said:
I think I'd call that difference significant enough- that's about the same spread in ft-lbs between M4 and the high carbide stainlesses. But either way, yeah, I guess I should have pointed out I wasn't making a perfectly fair comparison. I've always thought of 3V getting its claim to fame for the much greater amount of toughness it can have by tempering down a few points more- it almost doubles by dropping to 60 Rc, which is still pretty hard for a chopper (compared to conventional/traditional wisdom of mid to lower 50's for simpler steels). I would assume Crucible follows the same line of thought considering how much higher they show the line for 3V on the graph.
Click to expand...

Good points. The way I see it, CPM 3V's claim to fame is the ability to stay very tough at 60+ rc. It is basically 5160 with some vanadium carbides, and more corrosion resistant. I'd imagine that if only 60 rc is desired, 5160 can do the same thing for far cheaper. So I would use 62 rc example with 3V, since this is the steel's claim to fame.

Bottom line, for a large 1/4" chopper, you're talking about $5 worth of steel for 5160, $60 for 3V, or $100 for M4 (yes, I bought these steels right before Crucible tanked). The more expensive steels only seem to make sense if the higher hardnesses are used, because they are not any tougher at the lower hardnesses. In general the cheaper the steel, the tougher it is. It is foolish to pay more if toughness is the desire.

I'm going to try 65.5 rc for my CPM M4. According to datasheets it has the same impact toughness as D2@60 rc but more strength, useful for thin edges. I know of a well-known knifemaker also starting to test this steel at very high hardnesses. Seems like after 30 years, things are beginning to pick up for M4 use in knives. Thanks to the competitions.
 
Last edited:
I have been using a M4 Mule since they first came out and have been impressed with it’s edge retention. :thumbup: :cool: :thumbup:



:confused: Does anyone know the Hardness of the M4 in the Mule? :confused:



Big Mike

”Scaring the tree huggers.”

Forest & Stream
 
theonew said:
As per Sal: 62 - 63.

Hey Big Mike I enjoyed reading a torture test you did on 3V and A2 on another forum. Have you tried the CPM M4 on the bags of sandblasting abrasive? If so how did it perform? Thanks.
Click to expand...



Thanks Theo. :thumbup: :cool: :thumbup:



When it comes to the Torture Test, I did not include the M4 Mule, :eek:


…once we start blasting again I will put it to the test. :)



Big Mike

”Scaring the tree huggers.”

Forest & Stream
 
Big Mike said:
Thanks Theo. :thumbup: :cool: :thumbup:



When it comes to the Torture Test, I did not include the M4 Mule, :eek:


…once we start blasting again I will put it to the test. :)
Click to expand...

Looking forward to it :thumbup: Big Mike's test was very cool and definitely worth checking out. If anyone needs a link send me a PM.
 
You must log in or register to reply here.
Back
Top