I contacted Scott Moore:
mooreknives@yahoo.com about this knife, as he is knowledgeable in this area. Scott is the person who has been a Mad Dog dealer for the longest time, and was in the brown water (littoral) navy in Vietnam.
Here is the story of the ATAK (Advanced Tactical Assault Knife) series of knives.
The first ones were made in CA, and were marked as is shown on the ebay knife. The CNSWG stands for Commander, Naval Special Warfare Group). Essentially all of these knives, about 300 in all, were sold to the USN. The USN insisted on a non-reflective coating (Kalgard was used) and a sharpened false edge (to insure penetration through body armor). This necessitated file work on the spine so that the blade had uniform flexibility throughout its' length. Serial numbers started at 1 for this group and were consecutive.
A small number of knives were made next, for a foreign country; these lacked the CNSWG marking. About 50 to 75 of these were made in CA. They are rarely encountered.
Mad Dog then moved to AZ, and continued production of the ATAK. He began a new serial numbering system, with the first knife being A 500 (the A standing for AZ). These still had the Kalgard coating, sharpened false edge, and file work. About 500 of these were made. There was a change to another coating, also a baked on finish, somewhere in this production run. The second finish is more matte. The idea was to make the coating more durable. In addition, the markings are now distal to the choil, instead of proximal to it.
The first two knives in the photo below are from the 'A' production run: A 605 and A 936; these then come from near the beginning and near the end of the 'A' series knives. The first has the Kalgard coating, the second has the replacement coating. All these knives, incidentally, even the CNSWG ones, have hard chrome under the black coating.
'A' series knives were sold to the USN and to civilians. There is no difference between the knives sold to either buyer. Mad Dog kept a record of the knives sold to the USN, and will provide provenance for a nominal sum if the knife is sent to him for examination and documentation.
The next change was dropping the black coating, the sharpened false edge, and the file work (since without the sharpened false edge the file work was not necessary). The USN was finally convinced that the ATAK would go through body armor just fine without the sharpened false edge. The markings on these knives is slightly different from the 'A' series, as can be seen in the photo below. The periods after each letter of the acronyms have been dropped, and the marking is two lines instead of four.
A knife of this type is third from the top in the photo.
The next change was to make the choil longer near the spine than it was at the edge, thus giving the choil a diagonal appearance when viewed from the side. This was done to provide more strength to the spine. At about the same time, a change in the hard chrome type was made; this can be identified by a shinier appearance, with the temper line easily seen through the hard chrome. The markings were changed again, to simply 'Mad Dog.' The bottom knife in the photo is of this type. The only change between this type of knife and current production is that the hard chrome has been changed back to a more matte finish.
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Here is a close up of the markings on the same four knives:
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Here is a close up of the file worked spine, and a plain one:
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Incidentally, if anyone is unsure as to what is meant by the term 'positive included angle' as used by Mad Dog, the top knife provides an excellent example of it. Let the vertical line of the handle be the y axis; draw the x axis horizontally at the proximal edge of the knife. You will see as you go towards the point, the edge of the knife, while straight, dips below the x axis. By convention, an angle in the clockwise direction is positive. The effect of a positive included angle is to increase the cutting ability of the edge while drawing it back; this is similar to the effect of a recurve, without weakening the blade. At least this is the manner in which I understand the concept.
Any errors in the above are entirely my fault. Any questions, comments or corrections are welcomed. In the hope that this sheds some light on this subject, I remain, yr. obt. svt.
Walt Welch
[This message has been edited by Walt Welch (edited 03-04-2001).]