First let's start by saying that the proverbial "do all" knife has never been made. Men have worked long and hard only to realize that for every action is an equal and opposite reaction.
You want a knife for chopping down trees? The blade must be very tough. This means though that the blade is not as hard and will not hold an edge very long.
You want a knife that will skin a 300 pound animal without need to be sharpened? Then the blade will be very hard and thus somewhat brittle. Consequently more difficult to sharpen when it does need it.
A fighting knife is not an outdoor survival knife! Don't buy a dagger and expect it to perform as a survival knife.
When selecting a knife, consider this for a moment. Just because the price of the knife is ridiculous does not mean that its better. The heart of the system is the materials used and the construction methods. For example, A blade that is ground will not be as hard or durable as a hammer forged knife. The difference is that a ground knife is taken from 'flat stock' steel (essentially a flat steel bar) and they then grind on it until the desired shape is met. A forged knife is heated to almost melting point, then pounded and slammed until a rough shape is met. Some grinding is required, however the molecular structure of the steel is "compressed" if you will. To understand this better, take a handful of wet dirt. Shape into something just rubbing it. Do the same with another handful but this time mold the wet dirt into shape. Now tell me which one is better. Finding a forged knife can be expensive and time consuming. I would recommend doing this yourself as I did.
Let's discuss the steels used in blade craft. Stay away from anything marked '440' or '440 stainless.' Let me explain. 440 stainless steel has three grades. Yup! You guessed it, A, B, and C. At the top of this list is 440A while 440C is at the bottom. Any quality Stainless 440 knife will have one of the letter designations. If not, than the knife just looks cool and that's about all it will ever do. If you do find a stainless steel knife that you cant live without, make sure it comes from a reputable name brand. Gerber has some very nice knifes as does Schrade, K-Bar, SOG. But this brings us to the endless debate. Stainless or Carbon Steel?
The debate over carbon steel versus stainless steel will rage forever. So get some information out so you can make an informed purchase. Carbon steel is generally tougher and it will hold a better edge, longer. It also tends to be heavier and depending on the treating process, more brittle. It will also rust and if not cared for, pits form or if neglected long enough, the carbon content will compromised. Resulting in an utterly worthless blade. The most common Carbon steel blends (for knives) in America are 1095, 1085, 1080, 1050, and 1045. These numbers have meaning. The first two numbers are something that escapes me right now but they are less important than the last two digits. The 95 means that 0.95% of the steel carbon. This means that the steel is very hard and also toward the brittle side but will hold a very sharp edge for a long time. 1080 is a little less hard and also less brittle. Its still a good steel and will hold its edge. 1045 is softer still and significantly tougher than 1095. It does not hold its edge very well but will stand some angry abuse. There quite a bit more to this than just carbon content, but this will get you started in selecting your high carbon steel knife. Keep your carbon blade oiled!
Stainless steels are by their very nature 'elastic'. Meaning they will stretch and bend and thus make an ideal steel for bridges. As far as knives go. There are several types and blends of stainless steel on the market today and some of them are very good. We have already covered the 440 range of knives briefly. So, Stainless steel is made by adding magnesium, chromium, copper, and several other types of metals to create a rust resistant steel. Stainless knives tend to be pretty hard and are also hard to sharpen. But remember, stainless is hard but its 'elastic' so it will take the extra chop on the tree. There is also the "high carbon" Stainless knives out now. the best way to explain this is this. Stainless is stainless because the carbon has been reduced and replaced by other hard metals. Because carbon takes a better edge and holds it longer they have developed high carbon stainless. Imagine looking at a closet full of basket balls. Do you see the gaps between balls? That would be the "old" stainless from the 1970s and 1980s. Today that same closet would look like golf balls. The point is that the steels have gotten so good that even the bad stainless will cut. It really comes down to how often you are willing to sharpen your knife. Stainless blades also tend to be hard on your stone. The blends and numbers of stainless steels are vast. So many in fact that we're going to concentrate on the most common. Gerber knives use a blend called 9CRV19MOV which is a very good steel. Basically what this means is that it has a lot of Chrome Vanadium in it. This is a high carbon stainless steel blade that will take a razor edge and hold it for a reasonable length of time of good usage.
If the materials are the heart of the system then the handle would be the right arm. A full tang, one solid piece with a sharp end and [extending the full length of the] handle attached at the other end is the best way, period. The Bear Gryllis knife is a three quarter tang and it seems to work well. I haven't broken it so it must work well.
In my kit I carry one 1095 carbon steel knife and one stainless steel knife. The combination works for most situations I will encounter. Not everyone has the extra cash to spend $1,700 on a hand forged Damascus, hand heat treated, and hand tempered knife. So I will throw a suggestion of what I carry. Aside from the 12 inch fighting knife I got in Pakistan, I carry in my kit a Mora Bushcraft knife. Its 1095 high carbon steel and is probably the best knife that I have. It takes a crazy sharp edge and will hold for a long time. I have shaved my face with this knife. I also carry around a Bear Gryllis ultimate survival knife. It has a 7CRV17MOV stainless steel blade and this will also take crazy sharp edge. I have shaved with this one too. The point here is there is no better knife, carbon or stainless. I prefer carbon steel but find that I use my stainless knife more often. I dread sharpening time though. The Mora knife was about $35. you can get the smaller version that I call the kitchen knife for about $10-15. The Bear Gryllis cost me a whopping $50 and has served me very well in the bush.
Keep your knives sharp. A dull knife is a dangerous knife. Choose well and I hope I cold shed some light on what some call a difficult choice. God bless and long live the Republic!
- M.C. in Arizona
JWR Replies: To clarify, I agree that 440A is a very good steel for knives and it has several advantages over 440C. For example, it has much higher edge stability (edge holding), and it is more resistant to corrosion. But in "real world" practice, a lot of 440A steel is used to make very inexpensive imported (read: Mainland China) knives that receive pitiful heat treatment, so their performance in actual use is quite poor. Granted, 440C has considerably much more carbon than 440A (1.0%, versus 0.6%, as I recall), so it can take a sharper edge. The tradeoff is lower rust resistance. In looking at the progression of 440A through 440C the edge properties go up, whilst simultaneously the rust resistance properties go down. These issues have been discussed at length over at CutleryScience.com. Some custom knives that cost $500+ are made with 440C. So it is overly simplistic to just say that 440A is "better." It all depends on what is done with the raw material. If the maker is cranking out lots of junk knives with lousy heat treatment, then the original grade of stainless steel is not the key factor.