Hendon Publishing - Article Archive Details
Written by TR Staff
sigarms just announced their new line of proprietary tactical knives for law enforcement. The SigTac® series includes three knives: 1) Tactical Auto; 2) Neck Knife, and; 3) Folder.
We tested all three.
SigTac Tactical Auto
The Tactical Auto is a true auto opening knife and as such is generally restricted to law enforcement. The Tactical Auto is slim, light and compact, yet it has a full, 3.1-inch long blade. The blade uses a modified clip point, an extremely useful design. The blade comes as either a straight edge or with 30% of the edge serrated, which we prefer. The blade has a black Nitron® finish. This is the same hard and wear-resistant finish used on Sig Sauer pistols.
The blade is made from ATS-34, one of the best hybrid stainless steels available, along with its twin, 154 CM. These high end
stainless steels have the best balance of toughness, hardness, corrosion resistance, edge retention, sharpenability...you get the point. Developed for jet turbine blades and adapted to hard-use knives, these high carbon, stainless steels are ideal for police patrol and tactical use.
The Tactical Auto uses aluminum handles with a matte black anodize finish. The handles are CNC machined with stippling that somewhat improves the grip. The handles have a lanyard loop.
The Tactical Auto uses a button release to open the blade. The knife opened positively and fully locked every single time. Even if the blade is held back to quiet the noise of snapping open, the spring pressure reliably moves the blade to the locked position. Even held in the just-unlocked position, the blade positively locks when then released.
The blade is locked by the release plunger engaging a notch in the rotating tang. It is held closed by the same release plunger engaging a notch on the other side of the tang. The Tactical Auto uses a spine-mounted safety to lock the knife closed. The safety simply blocks the release plunger from being depressed. This safety does not, however, serve as a double lock once the blade is open.
Once open, the tang seats against a cross-pin allowing the blade to exert considerable force in the cutting direction. In the opposite direction (the false edge exerting pressure) the blade is locked open by the plunger held by spring force into the tang notch. While the lockup is firm and positive, it is not the strongest in this direction. Care should be exercised when using the false edge.
Oddly, the pocket clip is not reversible. It could have easily been made ambidextrous by drilling and tapping two holes. Since most right-handed officers carry the knife in their left pants pocket, we tried to deploy the Tactical Auto from the left side. This means the knife needs to be rotated after it is pulled from the pocket. And it also means the blade release must be depressed with an index finder, instead of the thumb. Under stress, frankly, that is a high risk move. By risk, this means the chances of dropping the knife, or having the blade open facing the body.
Understandably, the auto release button is small, (just 3/16ths in diameter), smooth and nearly flush with the handles. All this means that opening the knife requires fine dexterity when deployed from the left side.
The back of the blade near the tang has deep and aggressive thumb jimping. The heavy jimping on the blade more than makes up for the generally smooth handles in terms of slippery or hard use grip.
The Tactical Auto is made in the USA. Overall, the knife was extremely well-made, tight-fitting, deburred edges, and extremely sharp. Knives are supposed to be very sharp from the factory, not just mostly sharp, and the Tactical Auto was. This is an excellent, general-duty knife, comfortable to carry and, of course, the blade is extremely fast into service.
The SigTac folder is a serious, full-size, duty knife. It has a 3.75-inch blade and oversize handles. The blade is made from AUS 8 and is available as either a straight edge or 30% serrated. We tested the partially-serrated knife, of course.
The Folder uses a modified Tanto blade. The cutting edge and the point are classic double bevel Tanto. However, the back of the blade is very arched, almost like a Sheepsfoot blade. This makes for an extremely wide 1.25-inch blade. Wider blades cut better.
The blade is also hollow ground for maximum sharpness. Since police knives are used more for cutting than chopping or piercing, a hollow grind may make the best police edge. The unground portion of the 0.125-inch think blade has a black Teflon finish.
The knife has an ambidextrous thumb stud. The blade opened easily and locked positively with both the right hand and the left hand.
The SigTac Folder uses the liner lock design to hold the blade open. This is not the strongest lock design, or even second strongest, but it is a common design in police knives.
Some fairly durable, hard-use knives also use the liner lock design, so lock strength is not the ultimate deciding factor. Perhaps more important with the liner lock knives is how easy or difficult the blade is to unlock when locked open. In some cases, the twisting motion of the grip will allow part of the fist, palm or fingers to accidentally unlock the blade while it is in hard use. This is bad. It can happen.
In this regard, the SigTac Folder gets high marks. Wearing Kevlar ® gloves, we tried to inadvertently unlock the liner lock but it never did. With bare hand grip we (carefully) tried to trip the lock but it never did. In fact, the serrated liner lock arm is so flush with the grip handles, that intentionally closing the blade takes some effort. On a liner lock, that is good news. This is one liner lock knife that opens easily, locks positively and stays locked until the operator wants to close the blade.
The grip handles have a reversible pocket clip and a lanyard hole. The Zytel handles have the exact same texture, and Sig Sauer logo, as the P226 auto pistol. The handles are finely stippled, probably too fine a texture to really help the grip. However, the significant palm swell, the slight taper toward the blade, the oversize handles and the molded double quillion make this a knife very easy to grasp and hold during hard use.
The AUS stainless steels are traditional stainless steels. AUS 6, with 0.65 percent carbon, is roughly comparable to 440A stainless. AUS 8, with 0.85% carbon, is roughly comparable to 440B stainless. All of the AUS steels have Vanadium, which the 440-series lacks. Vanadium improves wear resistance and hardenability.
The AUS 8 alloy won’t hold an edge like ATS-34 and 154-CM, which have 1.05% carbon. It is a bit softer and may be a bit tougher. ATS-34 and 154-CM have less chromium than the AUS and 440 stainless steels but more carbon (hardness, edge holding) and more molybdenum (hardenability, toughness).
The hallmark of AUS 8 blades is razor sharpness, and the SigTac Folder came this way from the factory. Knife enthusiasts have a number of quaint ways to describe extreme sharpness...shave arm hair, etch thumb nail with only weight of blade, cut through paper on edge with only weight of blade. The SigTac Folder was among the sharpest knives we have ever reviewed, perhaps the sharpest.
The extreme sharpness of the Folder was due in large degree to the AUS 8 stainless steel alloy. The good news is AUS 8 is pretty easy to sharpen. The bad news is AUS 8, a typical lower carbon stainless, does not hold an edge well.
The SigTac Folder is made in Seki, Japan. If you carry one of the SigArms pistols, you will certainly want to carry this tactical folder. It has enough great features to carry even if you don’t use their pistols, and an absolute must if you do.
SigTac Neck Knife
The Neck Knife is a fixed blade that comes complete with a Kydex sheath. The sheath is designed for both belt carry and a neck carry using a chain. The knife uses a three-inch blade and is 6.6-inches overall. It is available as either a straight blade or a 30% serrated blade.
The blade is made of AUS 6 stainless steel with a black Teflon® coating. AUS 6 is a low carbon stainless steel. While it is a soft, low cost alloy, its biggest advantage is corrosion resistance.
AUS 6 is clearly a marine-quality, underwater-oriented knife material. With a full Teflon coating, the clear emphasis on this knife is utility with corrosion resistance. This is important for a knife designed to be worn next to the body.
The Neck Knife is fairly small and compact. It has G10 handles and two heavily jimped portions of the handle and blade, in the index finger groove and the thumb rest on the blade back. The knife was somewhat sharp and probably sharp enough. The small size of the handles prevented the knife from being used in high leverage, hard use chores.
The Neck Knife is made in Taiwan. Overall the Neck Knife is light and wearable. It will be there when it is needed.
Photos courtesy of SigTac.
Published in Tactical Response, Jan/Feb 2005
Rating : Not Yet Rated
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