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Went camping this past weekend and took my M4 Mule (with Micarta scales). I used the knife for basic bushcrafting. I made feather sticks, tinder by scrapping the inside of bark and camp tools from small tree limbs to name a few things.

The knife would not keep a keen edge. It would keep workable edge that could be stropped back to a shaving sharp edge but as soon as I started to cut something the sharp edge would be gone. I have read about the M4 steel knives that are used in cutting competitions and how the steel holds a shaving sharp edge while being used alot harder than I used my M4 mule.

Has any body else noticed this with their M4 Mule?

Wish I had one....

Jeremy McCullen wrote:Went camping this past weekend and took my M4 Mule (with Micarta scales). I used the knife for basic bushcrafting. I made feather sticks, tinder by scrapping the inside of bark and camp tools from small tree limbs to name a few things.

The knife would not keep a keen edge. It would keep workable edge that could be stropped back to a shaving sharp edge but as soon as I started to cut something the sharp edge would be gone. I have read about the M4 steel knives that are used in cutting competitions and how the steel holds a shaving sharp edge while being used alot harder than I used my M4 mule.

Has any body else noticed this with their M4 Mule?

I don't have a Mule but I got the Manix2 with M4. I was VERY disappointed with the edge holding ability. That was the main reason I wanted that knife. I used it and sharpened it as needed. Now, believe it or not it holds an edge like I think it should and as I expected. I don't know why. Work hardening? I still haven't decided if that is a myth, wives tale, truth or what. Anyway, try to keep an open mind for a while and see if your edge retention gets better. If someone said what I just did I would think they were crazy or just stupid so if you develope that opinion of me DON'T THINK YOU'RE THE FIRST. :D

Jack

Strange, I experienced no retention (or chipping/rolling) issues with both M4 Bradleys I have. (I remember we discussed M4 and its issues on the Bradleys widely already) Heattreating and tempering might be extra precise processes on this particular steel I suspect.

Tomas

jackknifeh wrote:I don't have a Mule but I got the Manix2 with M4. I was VERY disappointed with the edge holding ability. That was the main reason I wanted that knife. I used it and sharpened it as needed. Now, believe it or not it holds an edge like I think it should and as I expected. I don't know why. Work hardening? I still haven't decided if that is a myth, wives tale, truth or what. Anyway, try to keep an open mind for a while and see if your edge retention gets better. If someone said what I just did I would think they were crazy or just stupid so if you develope that opinion of me DON'T THINK YOU'RE THE FIRST. :D

Jack

Haha, I think you're crazy. But, I heard and experienced that before. Sometimes you have to get(sharpen) past that bad steel caused by higher heat treat temps near the edge and into some good steel.

I do not have the mule but I have a few M4 blades and no experience like yours, but I have heard some postulate that factory edges *can be* potentially defective in that sometimes the person sharpening them allows too much heat build up and this tempers the edge.

Some people Immediately regrind their new knives by hand for this reason. (to put on a good edge with no power tools and therefore no elevated temperatures).

I will tell you, that I generally am eager to put my own edge on every knife and it does seem to take a lot more time to get to the second sharpening than it did to get to the first sharpening after purchase. This seems true of every steel I have tried though...

I've got a couple of the M4 Mules, one cord-wrapped and one I stuck CF scales on. Both have been used a lot harder than you describe with no such issues. It sounds to me like you have a wire edge (i.e. a burr along the edge) that you are aligning by stropping but is too thin to stand up to harder use than shaving hair. M4 is tough enough to have a really stubborn burr. If it was mine, I'd start by running the blade edge down on a medium grit stone until the edge was flat, then sharpen it alternating sides to avoid a burr.

Its not zdp-189 but it's tough. Compared to some rugged steels like 1075 or O2 it holds a nice edge.

unit wrote:Some people Immediately regrind their new knives by hand for this reason. (to put on a good edge with no power tools and therefore no elevated temperatures).

This would be me. :D I've had so many factory edges that were wanting that the first thing I do is sharpen a new knife. I reprofiled/sharpened my M4 Mule to 20 degrees included. It's now got a 30 degree microbevel on that. Edge holding has been superb.

Gordon

I'd be happy to buy that knife from you if you don't like it.

Skunker wrote: ↑

Thu Jan 09, 2020 7:35 pm

I'd be happy to buy that knife from you if you don't like it.

Welcome to the forum,
And you realize the post you're replying to is almost nine years old??

Test another (decent)steel with similar(mule) geometry on the material you're using the m4 on. That would be the real test.

gOT 3 MULE TEAM #3 s90v AND very satisfy!

Wartstein wrote: ↑

Fri Jan 10, 2020 10:41 am

Skunker wrote: ↑

Thu Jan 09, 2020 7:35 pm

I'd be happy to buy that knife from you if you don't like it.

Welcome to the forum,
And you realize the post you're replying to is almost nine years old??

The things people will do for a M4 mule

Well, you have to rule out the sharpening, if you're just burnishing the edge to death on ceramic and never making a crisp new apex by cutting steel to establish a fresh new apex than it won't work as good as it could.

With a couple exceptions, my sharpening has always been the issue in situations like this.

I don't think the M4 mules were as hard as subsequent M4 knives. At least based on my subjective experience comparing my m4 mule with my Gayle bradley 2.