Spyderco Forums

I spent many hours trying to find the hardness of the MT38 mule in M398. I could not find one thing.

It is wonderful to have Larrin Thomas addressing the metallurgy of steels, in particular to knives. Unfortunately we cannot buy one piece of treated steel from Larrin. Not what he does. Of course he does a lot of work to process the steel. His conclusions are based on his experience, viewpoints, and opinions. I think his view of a steel in a knife is one that has a good chance in production. I am a risk taker so if I break a fragile knife I own it.

I think the lack of info is due to the lack of wide distribution of the MT38. From what I can gather many were referring to Larrin and his opinion that M398 is no better than M390 more or less.

I read in a thread that Sal answered some who wanted to know the hardness of the Magnacut mule. 62ish HRC.

I bought my Rex 76 on the secondary when I found the HRC for that. Did not pay much more than a Mule Cost at issue with shipping. And I did not get a pig in a poke.

Spyderco does a very good job of providing access to many steels, and even some not in production in the form of mules. I have two of those MT48 mules in my cart, I will pull the trigger if I can get info on the hardness and if I get a response from Spyderco about the dreaded "Red message of death" when I try to check out.

Thanks in advance for any info.

check out this post. Best list I know of.
viewtopic.php?f=15&t=89583#p1519432

To add, Spyderco tends to run their steels a little harder, assuming that we're using most of their knives for cutting, not twisting or prying. And mules get that treatment maybe even a bit more than usual. So when another big brand is heating M4 to 60-61HRC, the spydies might be 63-64 (62 is in that post but I've heard from a number of folks in the 63-64 range).

I defy you to find a factory knife manufacturer who does more to optimize heat treatment. They're putting out special runs of 15V and AEB-L after setting up specialized heat treats from custom maker BigBrownBear, after years of him showing his knowledge and experience. This is not a name, it's specialized protocols with some pretty impressive results, and Spyderco is more open about this testing (and welcomes it more on the forums) than any other factory maker on Earth.

If a knife comes out with an iffy heat treat, or even just an okay one, we suss it out here (also happens in the bladeforums spydie area, but especially here), and revisions are often made based on forumite suggestions, especially if presented with data. Cliff Stamp, Jim Ankerson, and indeed the indomitable Larrin Thomas have been regulars on this forum and directly influenced purchases, designs, and heat treats.

So if you care about this stuff, not just the hype, but real world results, you're in the right place.

The mule forum is also the best place to get eyes on concerns about steels and their heat treat, it's really a good portion of the point for having it and the Mule program at all. I believe that the vast majority of folks in this group would agree.

Thanks,

Just a simple number for HRC is all I am looking for. Twosun has one at 59HRC and it is not much good. Herman does 62HRC and others have customs made at 64HRC that they really like. BBB makes a knife in M398 at 66HRC.

I am no expert nor have I tested mine but, after sharpening it doesn't feel soft. I have had a ton of M390/20CV/204P cross my path and they all seemed to have rough burr removal. This mule seems to be just right as it took me less than 5 minutes to apex and strop it to hair whittling. I have had one other knife in 20CV before and it sharpened similarly and it was 64HRC. I would suspect that it is around there or maybe the microstructure and added elements help give it a better edge.

I will see if I can get it tested from one of my knife buddies and post the results. In the meantime, I would say it is definitely above 62 from sharpening alone but, dont quote me on that as I am no expert.

A friend of mine posted the hrc on his IG story. He tested the 15V manix i sold him at 65 and the m398 mule was 64.

Hi Murkyocean,

Welcome to our forum.

sal

Thanks to all who replied. 64 seems to be a sweet spot in the custom arena. Mules are basically customs too. Now if I can just get the Red Screen of You Bad Boy gone I can order those in my cart.

Hey TTFulltimer,

We generally don't display hardness for a variety of reasons. Sometimes one of your members here will test a blade and I will occasionally test one and share, but generally I don't do that. Most here have learned to trust that we're getting as much performance out of the piece as is possible that we're offering to you.

sal

double tap

sal

sal wrote: ↑

Fri Mar 03, 2023 12:58 am

Hey TTFulltimer,

We generally don't display hardness for a variety of reasons. Sometimes one of your members here will test a blade and I will occasionally test one and share, but generally I don't do that. Most here have learned to trust that we're getting as much performance out of the piece as is possible that we're offering to you.

sal

Over 20 years as a butcher and wore out many a knife, and never once knew or needed the HT of said knives. Also actually never knew what the steel in the knives I used was other than “high carbon”
Love the offerings of steel’s nowadays but steel type is enough for me.

sal wrote: ↑

Thu Mar 02, 2023 12:29 am

Hi Murkyocean,

Welcome to our forum.

sal

Thank you Sal. Glad to finally join the club!