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Extrema Ratio Selvans Expeditions

Extrema Ratio Selvans*** Expedition

 A brief overview by BCT

The Extrema Ratio Selvans Expedition, a 

newer model* (for the sake of brevity here on in I will refer to the Selvans Expeditions as just the "Selvans" BUT do NOT confuse this Selvans with the other version is the Mil C 13924) and a tip grind similar to the ONTOS.

The LASER engraving takes on (sorry you can't really see it here) that typical golden coloration of the reaction of the beam with Böhler's N690, just like the same coloration for all of ER's "desert warfare" markings.

The original Selvans which has been around for some years. Not as long as the infamous ONTOS military survival knife as shown below. (note the incredibly thick blade of the ONTOS, a proper military survival knife)

(levering doors open with this beast no problems!)

but none the less a long time.

Why? Because it simply works, that's why.

Let's take  look at the design now that the Expedition version is out. What are the differences?

 The blade is stone washed rather than having the Mil Spec grade Mil C 13924 black oxide coating as seen for the regular Selvans (there is nothing regular about these knives). 

As far as I can tell by eye, the surface is just how it would come from heat treatment protocols and then a quick surface clean via the "stone washing machine". Do not confuse what people are calling "stone washed", when they mean etched and then stone/abrasive cleaned, which will not happen with N690. Also while on that matter, NO stone washing is a "coating". This is incorrect to refer to such treatments as "coatings" they are either surface etched (chemically removing a part of the surface possibly revealing some crystalline structures) and then abraded via "stones"-either natural or synthetic  carbide or similar abrasives. But it is NOT a coating as in PVD coatings or PTFE type coatings, Cerakote etc.

And ordinary stone washing is simply a surface abrasive technique.

Now not having to prepare a blade for a MilC 13924 Black oxide will save many steps.

So why is the Selvans Expedition (series) "cheaper" (that/those words I never mention on the channel) than the regular Selvans? Without the fire steel and extra pouch etc.?

More than likely because of the requirements for a Mil  C 13924 surface preparation and application of the black oxide to military specifications is a lot more time consuming than simply stone washing a heat treated blade. To apply a Mil C 1394 grade black oxide, the blade must be very clean for a start, then probably because it is an anti-corrosive steel, the N690, it will mot likely undergo a hot salt bath application of oxide treatment, then several washes and other processes such as a dilute chromic acid bath wash as well, according to this specification. These steps are not for free. Of course there are black oxide treatments that do not have to satisfy Mil C 13924 but that is not what they are doing with their knives because the majority of end use is military, not civilian. I do not know this for 100% fact however, I'm sure I'm not too far off base.

Post heat treatment, N690, will have a dull blackened surface (like many steels) and usually this is totally removed by manufacturers as a prerequisite to further surface treatment/finishes can be applied. 

Progressing from this post heat treated surface and then simply stone washing, leaving a partial original darker surface amidst the abrasion past any heat treatment surface, could be a way to reduce costs without compromise to the surface.

Besides that, the surface will still be anti-reflective, maybe not as much as a Mil C 13924 standard but for civilian usage more than good enough.

Anyway, that's just my guess as they never told me any of this. Just based upon being in several knife factories and watching what goes on.

The blade of the Selvans is still non-reflective and still made from Böhler's N690 stainless steel.

However, now the Selvans Expedition comes with a remodelled sheath which has a good sized fire steel and a generously sized pocket to fit all sorts of useful things, making it a one stop survival solution**, to grab and go.

Full Molle compatible for multiple carry options.

Excellent attention to quality stitching throughout the sheath. This is one thing this manufacturer does not do and that is scrimp on the sheathes they make.

For those unfamiliar with the Selvans, this model is a sort of "follow on"/modification of the military survival knife the ONTOS with various features suitable for the civilian:

A longer handle/grip which also features a butt end to really hold the hand there when vigorous work in undertaken.

Lots of grip positions are possible with the Selvans.

A dedicated region of the spine to strike a fire steel (see the two "sparks" laser engraved onto the blade surface).

A more rounded tip profile and thus less of a "tanto" style compared to the ONTOS. (see above and below images)

Ontos on the left, Selvans Expedition on the Right. Note the overall much reduced blade thickness of the Selvans compared with the ONTOS. This will greatly aid cutting simply due to a better cutting geometry from this high sabre-like grind.

Don't think the Selvans Expeditions is some "weaker" brother of the ONTOS, no chance the spine is still 1/4 thick.

Weighted towards the tip for better chopping characteristics.

BTW does the Selvans or the Expedition version replace the ONTOS? I very much doubt this because as a military survival knife, the ONTOS is shorter in length and hence just a bit easy to carry plus with the serrations on the spine it can be rapidly deployed to cut line. Plus the ONTOS rear can be used as a glass breaker or a "persuader". This is no such feature on the Selvans Expedition, which is much more in line with a civilian tool as apposed to something clearly military in end usage.

There is less likely any chance on injury from the Selvans Expedition as there is only one cutting surface.

Handle, (virtually) indestructible Forprene elastomeric polymer.

The Selvans, like the ONTOS (it's name is even more descriptive) is more of a outdoors tool than anything that looks like a regular outdoor knife. It is akin to the foreigner's version of a Japanese Nata or Kanenori type implement. In other words, a big wide garden/agricultural tool but like the Nepalese Kukri, one can chop trees down with it and build a house with it (seen it with my very own eyes in Nepal).

So because of the blade geometry, the Selvans can be swung better than the Ontos (See video) due to the longer handle.

The weight distribution (see 2 images directly below) on the blade facilitates the action of chopping and thus making it efficient as the greater mass is delivered towards the tip and not the grip.

The broad but higher sabre grind is better for jungle work, eg just look at parangs etc. No parang or machete has a tip like a western style knife, ie "pointy", that is because there are many things you can cut better by "pushing" the end of the knife blade.

These "things" are like a cross between a small hatchet and a big knife. Hence ONTOS meaning "thing" in Greek. However, unlike the Nata or a Kanenori, the Selvans has the thickness of a Kukri  (but not the length, no kukri is that short) and requires somewhat more skill to prepare food with it (if your only edged tool at hand). I have seen workers deftly peeling paw paws with machetes and parangs; all is possible with the right skills at hand. 

Stay tuned  for how the Selvans Expedition does on food prep.

The Selvans Expedition in detail:

Stick around!

*** "Selvans" is the Mythical Etruscan Forrest God.

** (potential weapon), knife/tool, something to start a fire with.