Q: Should I buy a Tango Fire4000?
A: Short answer: probably not. The Tango Fire4000 has loyal owners, but many of them have never used anything better, so they have nothing to compare it with. Below, we explain what’s wrong with the Tango Fire4000 and what to buy instead.
Q: What problems does the Tango Fire4000 have?
A: These are the Tango Fire4000’s eight biggest problems:
No built-in environmental sensors. The Tango Fire4000 can’t measure temperature, pressure or humidity, so you depend on your mobile phone or a Kestrel to get that data. More info here.
A $130 Sig KILO2200 handheld outranges the Tango Fire4000. The Tango Fire4000 costs $1,500 and ranges less far in real-world use than a $130 Sig KILO2200 handheld. More info here.
Excessive beam divergence and a diagonal beam pattern. The wide beam can easily hit brush, trees and ground around your target, leading to potentially wildly inaccurate readings. More info here.
A continuous ranging bug that can stop updating your firing solution. The display keeps showing new ranges, but your firing solution stops updating, with no warning. More info here.
An inclinometer bug that can make the Tango Fire4000 use your phone’s angle instead of your rifle’s. A firmware bug causes the Tango Fire4000 ballistic calculator to use the angle you’re holding your phone, rather than the angle you’re holding your rifle, as the shooting angle. Obviously this can lead to wildly inaccurate firing solutions. More info here.
A manufacturer that hasn’t fixed the Tango Fire4000’s bugs. Owners reported both bugs publicly months ago, and Tango Innovations still hasn’t fixed them. More info here.
Tango Innovations is moving the ballistic software to a cloud-based app. You need an internet connection to load new bullet data. More info here.
Poor customer support. Owners say the company tells them they’re wrong instead of helping them. More info here.
Q: What’s the best alternative to the Tango Fire4000?
Q: What’s better than a Tango Fire4000?
A: If you already own a good handheld laser rangefinder, your rangefinder probably outperforms the Tango Fire4000. You just need a way to mount it on your rifle. The Sightlok RF-1 rangefinder mount holds your rangefinder on the rifle. Put your rangefinder in the mount, attach the mount to your rifle, close the protective cover, and co-witness the rangefinder to your scope. The mount costs $250, $1,250 less than a Tango Fire4000. The finished setup looks like this:
Q: What about the Tango Fire4000 vs the Vortex Impact 4000?
A: We think the Tango Fire4000 is the better of the two. Its wired remote doesn’t drain batteries or need slow re-pairing like the Vortex Impact 4000’s Bluetooth remote does. Neither would be a top recommendation.
👉 Below you’ll find the full breakdown, with field reports from owners on shooting forums and answers to the questions buyers ask most.
Or jump straight to an answer: Is the Tango Fire4000 worth it? · How far can the Tango Fire4000 range? · What does the Tango Fire4000 do better than the Sightlok RF-1? · Which rangefinder should I buy instead of a Tango Fire4000? · See all FAQs
1. The Tango Fire4000 Has No Built-in Environmental Sensors
Sig Sauer builds environmental sensors into every BDX-enabled handheld rangefinder from the KILO3K up. Here is what Tango Innovations says about the missing sensors on its own website:
If Tango Innovations had designed the Tango Fire4000, its engineers would know why they left the sensors out. Because Tango Innovations can only guess at the reason, we believe a company in China designed the Tango Fire4000, even though the label says “Designed in U.S.” If the label is wrong, you have reason to doubt Tango Innovations’ other claims about the Tango Fire4000.
Temperature, pressure and humidity all change your firing solution. Without sensors on the Tango Fire4000, you depend on your mobile phone or a Kestrel to get that data.
2. A $130 Sig KILO2200 Handheld Outranges the Tango Fire4000
Here are real-world ranging distances for both units:
| Target | Sig KILO2200 ($130) | Tango Fire4000 ($1,500) |
|---|---|---|
| Ranging trees | 1,600 yards | 1,500 yards |
| Ranging animals (deer/elk) | 1,300 yards | 1,200 yards |
3. The Tango Fire4000 Has the Same Wide, Diagonal Beam Divergence Problem as the Vortex Impact 4000
Tango Innovations doesn’t publish a beam divergence figure for the Tango Fire4000. Field reports describe the same excessive beam divergence and diagonal beam pattern as the Vortex Impact 4000. (Side-by-side beam numbers are farther down the page.)
Here’s a photo of the Vortex Impact 4000’s beam, taken through night vision. Vortex publishes the Vortex Impact 4000’s beam divergence: 2.0 x 0.2 MRAD at a 45° angle. Look at how wide and lopsided the beam is:
The Tango Fire4000 shows the same real-world symptoms in the field, and we think it may actually share the same laser unit that’s used by Vortex.
The Tango Fire4000’s wide beam can hit branches, grass and ground in the same pulse as the target. When the beam hits those objects, the Tango Fire4000 can give you a false or blended reading instead of the distance you wanted.
4. The Tango Fire4000 Continuous Ranging Bug Can Stop Updating Your Firing Solution
Owners first reported the continuous ranging bug on Snipershide. The bug can start when you hold down the remote or the range button for continuous ranging. After 2 to 3 ranges, the Tango Fire4000 can stop recalculating your firing solution while the display keeps showing new ranges, so you can take a shot on an old firing solution.
5. The Tango Fire4000 Inclinometer Bug Can Use Your Phone’s Angle Instead of Your Rifle’s
Owners have also reported the inclinometer bug on Snipershide. A Tango Innovations representative posted this response:
A firmware bug causes the Tango Fire4000 ballistic calculator to use the angle you’re holding your phone, rather than the angle you’re holding your rifle, as the shooting angle. So, for example, if you’re holding your phone vertically, as one commonly does, the ballistic calculator thinks your rifle is pointing straight up in the sky rather than toward the horizon. Obviously this can lead to wildly inaccurate firing solutions.
6. Tango Innovations Hasn’t Fixed the Tango Fire4000’s Bugs
Tango Innovations representative Mfelici1 follows the Snipershide thread, but Tango Innovations hasn’t announced a fix or a date for one. Tango Innovations should treat both bugs as serious, because either one can put a wrong firing solution on your screen, and should consider a recall. Sig Sauer or Vortex would at least acknowledge bugs like these and announce plans for a fix.
7. Tango Innovations Is Moving the Tango Fire4000’s Ballistic Software to a Cloud-Based App
The Tango Fire4000 shipped with the “AB Synapse – BOSS” app, which is no longer in development. Tango Innovations is moving owners to Applied Ballistics Quantum, a cloud-based app. Depending on a cloud app means you need an internet connection to grab drag curves or new bullet data, often not practical when you’re out in the field.
8. Owners Report Poor Tango Fire4000 Customer Support
You can read owners’ comments about Tango Innovations’ support on Snipershide and below this article. One commenter wrote: “I’ve been texting back and forth with Marcus with the Tangoinnos company… after reading this blog post I realize I’ve been gaslit.”
Sig Sauer, by contrast, backs its electro-optics with the Infinite Guarantee™, a fully transferable lifetime warranty.
What to Buy Instead of the Tango Fire4000
You don’t need a dedicated weapon-mounted rangefinder. Mount a handheld rangefinder instead. If you don’t own a rangefinder yet, here’s the cost:
| Component | Cost |
|---|---|
| Sig Sauer KILO2200 BDX handheld rangefinder | $130 |
| Sightlok RF-1 mount | $250 |
| Total | $380 |
| Tango Fire4000 | $1,500 |
The KILO2200 has no environmental sensors. For built-in sensors, choose a Sig KILO3K or higher.
The handheld setup saves you $1,120, about 75% of the Tango Fire4000’s price, and the cheaper setup is also the better one. If you already own a decent handheld rangefinder, you only pay for the $250 mount.
Almost any handheld rangefinder works with the Sightlok RF-1, so you’re not locked into one brand.
Build a Better WMLRF Than the Tango Fire4000
With the Sightlok RF-1, you can:
- Use the handheld rangefinder you already own
- Get a better beam than the Tango Fire4000 from almost any decent handheld, like the $130 Sig KILO2200
- Quickly detach your rangefinder when you have a target you want to range that you don’t want to point your muzzle at. When you’re done, clip it back on. All without losing the co-witness between the rangefinder and the scope
See how to turn the rangefinder you already own into a better WMLRF than the Tango Fire4000
Is the Tango Fire4000 worth it?
No. A good handheld rangefinder in a Sightlok RF-1 mount does the job better for much less money. See the eight problems at the top of this page for the reasons.
How far can the Tango Fire4000 range?
See problem 2 for real-world ranging figures.
What’s a key advantage of the Sightlok RF-1 over the Tango Fire4000?
With the Sightlok RF-1, you can range a target without pointing your rifle at it. The Tango Fire4000 is one unit fixed to your rifle. To range anything, you have to point the rifle, and the laser on top of the rifle, at the thing you want to range.
Will recoil damage my rangefinder in a Sightlok RF-1?
Almost certainly not. Handheld rangefinders are designed to survive drops of about 3 feet, and the impact from a 3 foot drop can generate several thousand psi of pressure. In the Sightlok RF-1, recoil presses on any one spot of your rangefinder about as hard as your thumb presses the range button, a few dozen psi at most. A few dozen psi is well under 1% of the pressure your rangefinder is built to survive in a 3-foot drop. At that margin, the chance of a .308 shot damaging a healthy rangefinder in the RF-1 is effectively zero. In two years of selling the Sightlok RF-1, no customer has reported a rangefinder damaged by recoil. Read the full recoil answer and watch the recoil test videos.
What’s an advantage of the Tango Fire4000 over the Sightlok RF-1?
The Tango Fire4000 is faster to range with. Its wired remote sits by your trigger hand, so you range with one button press. The Sightlok RF-1 has no remote, so you press the rangefinder’s own button with your support hand, and that hand comes off the rifle. On a bipod or a bag, you’ll hardly notice the difference. Standing, kneeling or braced against a tree, you break your hold to range. Pressing the button by hand is still faster than waiting on the Vortex Impact 4000’s Bluetooth remote, but slower than the Tango Fire4000’s wired remote.
If I don’t already own a good handheld rangefinder, which one should I use with the Sightlok RF-1 instead of a Tango Fire4000?
Pick a rangefinder based on how far you shoot. For ultra-long distances, you may need a Sig KILO8K-ABS or a Sig KILO5K. Most shooters can use almost any decent handheld rangefinder, and the rangefinder doesn’t have to be a Sig. Plenty of ordinary handhelds outrange the Tango Fire4000 and have a better beam. The $130 Sig Sauer KILO2200, for example, has a better laser and better software than the Tango Fire4000. Work out the distances and conditions you shoot in, and buy a rangefinder that handles them. Most shooters don’t need a KILO8K-ABS and would never use most of its range.
How does the Tango Fire4000’s beam compare with the Sig KILO2200, KILO5K and KILO8K-ABS?
Every Sig unit below has a published beam divergence figure. The Vortex Impact 4000 is included for reference:
| Rangefinder | Beam divergence | Beam pattern |
|---|---|---|
| Tango Fire4000 | Not published | Field reports describe excessive beam divergence and a diagonal pattern |
| Vortex Impact 4000 (for reference) | 2.0 x 0.2 MRAD | “Slash-shaped,” canted 45° |
| Sig KILO2200 | 1.4 MRAD | Round |
| Sig KILO5K | 1.3 MRAD | Round |
| Sig KILO8K-ABS | 1.2 x 0.25 MRAD | Rectangular, wider than tall |
What about recoil? Won’t my rangefinder be damaged if I mount it to my rifle?
To understand the probability of damage from recoil to your rangefinder, we must take into account how much force is being applied by common rifle cartridges like the .308, how that force is distributed, and roughly how close that comes to the amount of force necessary to actually damage your rangefinder.
How much force?
The amount of force is not that great. For example, in the case of a .308, the cumulative force of the recoil is about equal to the force of you picking up your rangefinder and squeezing it hard for a few thousandths of a second.
How is the force distributed?
Beyond the actual amount of force is an even more critical factor: How the force is distributed. Sightlok RF-1 uses 3M impact-absorbing rubber to hold the rangefinder and evenly distribute the recoil forces while simultaneously shielding sensitive areas like the buttons, the laser aperture lenses, the ocular, and the ocular lenses from impact. Lastly, when the rangefinder is held in the RF-1 mount, recoil force travels straight back along the bore axis, rather than to corners or edges where impact forces can cause more damage. The result of these mitigating factors is that recoil generates about the same amount of pressure on your rangefinder as you exert when you press the range button.
Typical standards for rangefinder durability
Handheld rangefinders are designed to survive drops of about 3 feet, and the impact from a 3 foot drop can generate several thousand psi of pressure.
How close does recoil come to causing damage?
In the RF-1, recoil presses on any one spot of your rangefinder about as hard as your thumb presses the range button, a few dozen psi at most. A few dozen psi is well under 1% of the pressure your rangefinder is built to survive in a 3-foot drop. At that margin, the chance of a .308 shot damaging a healthy rangefinder in the RF-1 is effectively zero.
No reported failures
In two years of selling the Sightlok RF-1, no customer has reported a rangefinder damaged by recoil.
Recoil tests on video
Below, a US military rifleman tests the Sightlok RF-1 with recoil from two common cartridges.
Sig Sauer KILO1000BDX versus .308 rifle recoil:
Sig Sauer KILO1000BDX versus 6.5 Creedmoor rifle recoil:
Who is Sightlok?
Sightlok publishes factual, unbiased reports and reviews on electro-optics gear, especially weapon-mounted laser rangefinders (WMLRF). We are the world’s leading independent expert on WMLRF options. We also design and build the Sightlok RF-1. Our goal is simple: help you find gear that fits your needs, and help you avoid gear that doesn’t.
Where does this information come from?
We base these reports on our own field experience with the products, on conversations with our customers, and on posts from respected members of forums like Snipershide, Rokslide and LongRangeHunting.
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A link or two to see who designed and manufactures the Fire4000:
https://apps.fcc.gov/eas/GetApplicationAttachment.html?id=7879019
(from https://apps.fcc.gov/oetcf/eas/reports/ViewExhibitReport.cfm?mode=Exhibits&RequestTimeout=500&calledFromFrame=N&application_id=HuxY3UutNSVUgxZFJpW9oQ%3D%3D&fcc_id=2BMHK-FIRE4000)
https://www.henrichtechnology.com/product/ballistics-computer/
Hey Julep, thanks for that tip. Yep, seems that Henrich, which sounds German, is the Chinese manufacturer, and they may even run Tango Innovations. Hope that’s not the case.
I’ve been texting back and forth with Marcus with the Tangoinnos company… after reading this blog post I realize I’ve been gaslit. Nonsense about the processor in the kestrel being too slow but it doesn’t work any better with the phone app. Very disappointed to read this but at least now I know I’m not doing anything wrong
Sorry to hear you’re not getting the answers you need from the company. Can you please provide more information about the problem you’re having?
I am having trouble with the 4000 it won’t hold zero and I have to constantly readjusting it, I am hoping they will replace it have a call in it’s been one days and no response yet.
Has your problem been solved?
At least one long-time Sniperhide member who had bad things to say about the Tango 4000 Fire WMLRF had his Snipershide account deleted. One thing you find almost universally is when people spend a pile of money on something, they want it to be perfect. They don’t want people criticising it. If you criticize their baby, they can get very upset and defensive, even denying serious flaws and problems. This is the sunk cost fallacy. The sunk cost fallacy is the tendency for people to irrationally defend their buying decision based on the fact that they’ve already invested a sizable chuck of money. If you want to critically evaluate the Tango 4000, this is a safe place to do it.
Just installed a fire 4000 and it’s very inaccurate in it’s dope by more than 30 yards, waiting for some one to get back to me, all the other data was no problem inputting in the fire 4000 it’s just off big time on accuracy, don’t know if it’s me or the unit I hope it’s a simple fix the unit is well built Donald.
Donald, really appreciate the feedback. Hope you get the issue figured out. Please follow up whatever happens!