For serious hunters and shooters, rangefinders are an essential, but often overlooked tool. We’ve become accustomed to either low magnification and bad image quality from small rangefinders, or hard to carry around and cumbersome rangefinding binoculars for better image quality. Some units are bulky. Some are slow. Some are inconsistent with their readings. Most are very hard to keep steady on a target to range without stabilizing it on a rock, backpack or tripod. Some check all those boxes. Now imagine a rangefinder that has none of these drawbacks. That’s the Sig Sauer KILO4K rangefinder.
Table of Contents
Sig Sauer KILO4K Specs and Key Features
- Dimensions: 4.1 x 3.1 x 1.6 inches (measured)
- Weight: 7.5 ounces (measured)
- Magnification: 6x
- Objective Lens Diameter: 22 mm
- Field of view: 6.5º
- Eye relief: 15 mm
- Battery life: 4000 ranges
- Max ranging distances: 1600 yards on deer, 2000 yards on trees, 4000 yards on reflective objects
- Price: $599 at time of writing
Sig Sauer KILO 4K Controls
The Kilo 4K has two buttons, a Power / Ranger button on the top and a Mode button on the left side of the device when viewing through it.
The buttons are intuitive and responsive, and becomes second nature to use on the fly as you get used to them quickly.
In addition to these buttons the Sig rangefinder has a lanyard attachment point, a focusing diopter and the battery compartment which accepts CR123 batteries.
Though the Sig Kilo4K is incredibly light, it is tough and built to last in the field. The rangefinder is has an IPX-7 waterproofing rating, meaning it can withstand being submerged in water that is a meter deep for up to 30 minutes, so it will certainly be able to withstand any weather conditions you may experience on a shoot or a hunt.
The tough but lightweight polymer housing with comfortable rubber additions to aid in grip, make it effortless to haul on a trekking hunt, and quick to grab and use when needed.
I love how compact and portable the unit is. Especially when you have gotten used to having to carry a pair of rangefinder binoculars, or a pair of standard binoculars with a rangefinder. Honestly speaking, I never imagined being able to just carry and glass with a rangefinder, but with the image stabilizing function of this unit, paired with good glass, magnification and clarity, I truly am able to just use it for glassing and ranging. Just before writing this review, I used this unit on a small one-day hunt, to first see how good it was before committing to using it alone on a bigger, longer hunt. It absolutely exceeded my expectations for stability and actually effective use, so much so, that I am planning a multi day hiking hunt, where I will only be taking this Sig rangefinder instead of binos.
I built the ballistic profile for my 6.5mm Creedmoor custom Remington 700 rifle (which is my hard-use workhorse rifle) into it, shooting the Berger 140gr VLD Hunting bullets at around 2820fps, and got a first round hit at 690m with the drop reading given by the rangefinder dialed into my scope.
Too Good To Be True
Using the Sig Sauer KILO4K Rangefinder for the first time feels almost like you have never used a rangefinder ever before. You struggle to comprehend what you’re seeing, and how much the absolute ease of use with the stabilized image has for handheld use. You wonder how you ever did before or would ever be able to use a rangefinder without the stabilization again.
Sounds like hype, I know. But when you are used to not even trying to range an animal free hand ever as you have been unable to accurately do it consistently, to actually being able to do it right away, is somewhat boggling to the mind at first.
Dawn of a New Era
The Sig Sauer KILO4K just made your current handheld rangefinder obsolete. This applies to any handheld rangefinder you use, even binocular rangefinders as they are just as hard to keep steady and get an accurate range on an animal at any distance when not mounted on a tripod or stabilized on a sandbag. With the Sig rangefinder, you do not need to have extra support anymore, you really don’t. This totally negates the need to carry a tripod for ranging.
Rangefinder Binoculars Pros and Cons
My binoculars with rangefinder built in has served me well over the years, or so I thought. Its principle virtue is that you can spot and range with the same item, and because binoculars need to be held with both hands, it is easier to try stabilize with elbows on a rock or other hard surface, but it was a still a hit ‘n miss process to get it stable enough and range the correct target. The extra magnification and larger field of view on the other hand, remains a pro that still makes it better to view through than the Sig rangefinder, however for ranging, that is not the case.
Testing the Sig Sauer Kilo4K in the Field
The Sig 4k rangefinder ships with a carry pouch and lanyard, although I prefer to have the carry pouch on my belt so I do not use the lanyard. You pop it open, pull the rangefinder out with one hand, hold it up to your eye pointed at the target and press the power / range button. And that’s it. It noticeably stabilizes the image, then ranges it on the second press. It requires no additional setup. That is just for getting a range though, for actual ballistic drop data, you need to setup and load your rifle and ammunition profile onto the unit.
The mode button guides you through a couple menu screens. Do you want to change the units, to you want to change the target acquisition to front favoring or through brush? What kind of rifle are you using: rifle, bullet, muzzle velocity, or ballistic coefficient? Then under each type of profile it gives you a bullet profile to load on as well.
The Sig Sauer KILO4K rangefinder is much more accommodating than you would expect. At the first push of the power button, Kilo suddenly reels in the image and it feels almost as if time slows down as the shaky image suddenly becomes fluidly smooth, then you find that you are easily able to put the reticle on the target or animal your want to range, press the button again, and quickly get a range and ballistic drop reading.
The Applied Ballistics Ultralite software allows the programming of up to 25 ballistic profiles for different rifles or ammunition setups, so you can change between rifles or ammunition with a quick selection and be ready to use it when changing the rifle or ammo. The AB elite also compensates for coriolis effect and spin drift so your drop will be accurate out to longer ranges too automatically.
The objective of the rangefinder contains a small ambient light sensor (ALS) that samples the brightness of the target image and adjusts the contrast accordingly in real time. This ensure no matter the lighting conditions, you always have a bright crisp image and you are always able to see the readout no matter the background.
The hyperscan mode of the Sig rangefinder allows you to scan targets at 4 times per second which significantly improves ranging performance at extreme distances, and helps you see from the range that jumps out at a little less than the rest that you know you are on the small target and not ranging past it as often occurs with steel targets.
To anybody who has some experience using rangefinders in the field this degree of forgiveness is astonishing.
How Accurate is the Sig Kilo4K Rangefinder?
Rangefinder are only useful in as far as they provide accurate results. According to Sig Sauer, the Kilo4K will provide line of sight modified ranges accurate to ±1 yard or
meter out to 500 yards and ±2 yards from 500 – 3000 yards.
I compared the Sig 4K to my other two trusted rangefinders and the distances it ranged were always within 1-2 meters from each other, and they have been proven to correlate to my rifle dope for quite a few years, so to me that accuracy is excellent and ensures that I will not be missing a target because of a inaccurate distance reading from the rangefinder if I kept the reticle on target.
That satisfied me, and with the drop readings I got from the sig rangefinder, I was able to hit targets out to 1200 meters on the range I tested it on when I wanted to test the distance. For the normal ranges I used in competition ranging from 280 to around 650 yards, when I was steady, I hit every target with the correct dope from the rangefinder. The shots I missed were all me, and nothing to do with incorrect ranges.
How Does the Sig Sauer Kilo4K Work?
SIG SAUER’s Gen II Lightwave DSP engine uses HyperScan, an advanced power management technique that provides the fastest scan mode refresh rate (4 times per second) at distances over 2 miles. The DSP engine’s latest generation field programmable gate array (FPGA) and sophisticated signal processing algorithms reduce false positives and detect weak or distant targets.
The BDX system simplifies determining the correct range and ballistics solution for first-round hits. An embedded Applied Ballistics Ultralight calculator allows users to configure up to 25 custom bullet profiles in the free BDX App and sync with their KILO rangefinder. Line of sight, elevation, and wind hold information are calculated and displayed instantly based on the active profile.
The rangefinder has five modes of operation: AMR, LOS, Archery, BDX-U (Applied Ballistics Ultralight), and BDX-X. When BDX-U is selected, you can pair your KILO you might download the BDX App, select a .264 caliber bullet, and choose a Berger 140 grain Elite Hunter bullet. This profile is then selected and saved. You will then configure the muzzle velocity, zero range, temperature, and altitude within the BDX App.
Applied Ballistics External (BDX-X) allows the KILO to be paired with an external Kestrel Elite or Garmin Foretrex device for more precise ballistic solutions beyond 800 meters. AB Elite includes support for Coriolis, spin drift, and other factors, while providing custom drag curves for the most accurate ballistic solutions in the industry.
Angle modified range (AMR) is the horizontal distance to the target, and is analogous to the “horizontal leg” of a right angled triangle. AMR, also known as “rifleman’s rule,” uses the line of sight (LOS) range and angle of incline to the target to calculate the horizontal distance the projectile travels between you and the target or animal. AMR is very accurate for shorter distances (i.e., < 400 yards).
LOS range is the distance to the target regardless of angle, and is analogous to the “hypotenuse” of a right angled triangle. When ranging in LOS mode, the distance is displayed along with the angle of inclination. This method is preferred by long-range shooters and hunters who want to use the LOS range and angle of inclination to calculate a very precise holdover using a ballistic calculator in a smartphone app and/or wind measurement device like a Kestrel.
Accessories for the Sig Sauer KILO4K
Because the Kilo4K is light, tough, portable, accurate, and has an excellent battery life it can be carried with you in the field when hunting all day. This is especially relevant in tag hunts where you never know when an animal will show itself and you need to move quickly to range and shoot it, as it may e your only shot for the season. Personally, I carry an extra battery with me in my hunting backpack, as you never know when a low battery will strike, and also a lenspen to keep the lenses clean and dry no matter the weather.
Sig Sauer KILO4K Pros and Cons
- Ease of use
- User friendly
- Accurate readings
- Stabilized image for hand-held ranging
- Excellent battery life
- Durable construction
- BDX-U and Applied Ballistics Elite integration
- Competitive price
- Would have liked to have Applied Ballistics elite built in instead of ultralite so it can offer ballistic solver solutions past 800 yards without needing a Kestrel too, but not sure how often that will be used without a wind meter if ever, so not a real issue.
Final Thoughts on the Sig Sauer Kilo4K
For hunters, the Sig Sauer Kilo4K is a dream come true. Avid hunters, be it with bow or rifle, are going to want to add a Sig Kilo4K to their kit, it will be invaluable when the pressure is on to make the shot that counts, or risk losing the animal for the season, or worse, even wounding it.
And at the $599 price, you simply cannot beat it for value considering all the features it provides compared to the much more expensive binoculars with rangefinder built in. It is without a doubt the best rangefinder for hunting available on the market today.
Given that hunters and shooters in general have become more clued-up about long range shooting and that our rifles, scopes, and ammunition have improved so much over the last 10 years or more, the Kilo4k helps bridge an important divide: between the ability of our rifle and ammunition, and our effective use of that full capability.
For me, this little Sig rangefinder is a blessing and will definitely stay put in my hunting kit.