Differences between the Extrema Ratio ONTOS and the ONTOS II

 Understanding the Differences between the Extrema Ratio ONTOS and the ONTOS II

Let's take a look at them!

Above, the mighty Extrema Ratio ONTOS

Seen above here: The New Extrema Ratio ONTOS II (shown is the N690 Expeditions version, there is also a Böhler S600 Tungsten alloy version as well-more on this later) . 

So what's the difference?

In order to understand the difference between these 2 models we will discuss the finer points of the original ONTOS, a knife which is still a current model from Extrema Ratio.

The Ontos was conceived as a hardcore military survival type knife 

and as such it's design reflects this. A Western styled Tanto, which had a convex ground edge placed upon it. The main part of the blade however is not totally straight and has the slightest curvature to it; combine this with a similar slight curvature of the tip cutting section and you have a formidable cutting piece. 

In order for excessive strength capabilities, the blade width is 6mm and a type of sabre grind, with the spine being reduced in two  key regions, (see below)

one just behind the tip to give this model fair to good penetrative abilities despite it's blade thickness. The spine is further reduced in a region after the hilt where alternating serrations have been placed, 

enabling it's capacity to quickly cut cords. The ONTOS is extremely capable of hard tasks and due to it's overall weight can also be used to chop effortlessly. 

Before I go any further, if you have not seen my extensive reviews of the ONTOS over the years then please check them out under the Play list of Extrema Ratio knives @BushCampingTools.

 

The geometry of the ONTOS is thus totally suited for such tasks as chopping hacking, cutting, levering, hammering, skinning and butchering, along with fire starting tasks. With a hand ground convex edge, the knife edge retains good functionality with heavy work on dirty objects and can easily be maintained in the field. 

The Ontos comes with an option to attach a small pouch which one can place a "survival kit" and diamond sharpening plate. I of course got rid of most of the stuff in this tin and replaced it with my own materials. Needless to say it is fully Molle compatible and also features a leg strap and like all of their scabbards there is much attention drawn to the quality of the stitching and robust nature of their design.

Now what about the new ONTOS II?

Above image showing the Böhler S600 version of the ONTOS II

Ok, so other than a name change, I feel the ONTOS II is a totally different knife than that of the ONTOS. It has been designed for an entirely different market/end use. 

For a start, the blade features a full flat grind which by default results in a substantially thinner profile than that of the ONTOS. One notices the blade is lighter in the hand and this of course has it's benefits for a knife which is practical to be used all day and not just brought out for an imminent survival situation and or emergency. The Blade of the ONTOS II has been re-engineered for cutting tasks. The tip is no longer that of a Western styled Tanto and more of drop point with good curvature which will allow for use as a skinning knife (if you had to). 

The serrations have disappeared and this region can now be used to break dead wood without unnecessarily dulling the primary knife edge (see my Kizlyar Supreme Survival knife reviews where Kizlyar Supreme also feature such a section on their spine of their survival knife). 

They (Extrema Ratio) have however left a good chunk of spine unaltered in order to provide a flat surface for light hammering and or striking surface for a baton. However, the ONTOS II is now basically in the large "camp knife" category- yes it can like all large knives be used in a "survival situation but why would you since if you plan to stay on a deserted tropical island (as I have) you would instead choose the Ontos as weight is not a consideration if one is not on the move.

With 2 options available, a N690 "Expeditions" model, equipped with molle/pals compatible sheath and a Malice strapped pouch and fire steel, what more do you want for your camping/hiking trip? Ok, so what more do you want?

How about the S600 Tungsten alloy tool steel version? What on earth are you are talking about???

Well here's the scenario, you like going out into the wilderness, you will be cutting stuff, all sorts of stuff and you want to move as light as you can for as long as you can then you may not take a sharpening device with you want an edge which will hold up against the most abrasive stuff you can throw at it like cutting mushrooms close to the ground where there is a high probability of the edge contacting stones etc. 

Then you want to process some wood and the only wood is stuff laying on the ground. This wood will never be as clean and free of dirt like fresh sawn timber or dead wood still on the tree, plus you may not have a choice here. Essentially you are taking a big knife made with a steel, of whose edge will resist damage to a greater extent better than N690 all things being equal. 

Now you are saying, heck why no just harden N690 to over 60HRC? Well if one does this then any stainless properties will go out the window because the higher the HRC for N690 the less resistance it has to corrosion and heck that's why you would choose N690 for such a knife if you plan on working in wet/damp conditions all the time and not a high probability of keeping the blade dry, then this might be case just to use a HRC 58 knife. That being said, S600 is not corrosion proof and one should keep it dry. So where will S600 shine? 

I'd say in dry dusty (and hence abrasive) environments, where little or no water can be wasted just to sharpen a knife. So in other words an arid/desert (as an example but of course not limited to) environment. So one's knife edge needs to stay sharp for longer in between being able to actually put it against a stone/device. 

There are of course trade offs with all high HRC knife steels and that is it will, by physics, take longer to sharpen compared with a lower HRC56-58 hardened and tempered blades. With S600 it has a proven edge stability-after all it is a tool steel which is used to cut other metals including other steels!

So if you don't know, what is in Böhler's S600?

So taken directly from Böhler's site

Just look at that elemental composition! It is of course the high Molybdenum (Mo), Vanadium (V) and Tungsten (W) percentages which give the S600 it's amazing characteristics and partake in carbide formation with the Mo also contributing to the overall toughness.  S600 is an alloy which can of course be hardened in the vicinity of HRC 65-67! at a tempering temperature of 540C, however, in the case of the Extrema Ratio ONTOS II S600, we have a more respectable and practical HRC of approx: 64, which is super hard but not insanely hard!  The S600 has also been cryogenically treated for optimal grain structure. Vanadium carbide generation and WC generation provide the basis for wear resistance with Mo improving the toughness.

More to come in the field so stick around!

BCT