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. More info here.
Excessive beam divergence and a diagonal beam pattern. Due to the excessive beam divergence, the laser 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 your firing solution from updating. 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. 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. More info here.
A company that doesn’t appear to support its product or its customers. We suspect Tango Innovations is basically the U.S. sales office for Henrich Technology, a Chinese company. More info here.
Q: What’s the best alternative to the Tango Fire4000?
Q: What’s better than a Tango Fire4000?
A: An increasingly popular solution to the “WMLRF problem” is mounting a handheld rangefinder to your rifle using a Sightlok RF-1 rangefinder mount.
The approach has some disadvantages. Overall, however, it’s a more flexible, modular, and cost-effective solution that, depending on the rangefinder you deploy, can actually deliver more accurate results in the field.
The finished setup looks like this:
The Sightlok RF-1 protects your rangefinder from recoil, bumps, and scratches. A polymer hood protects the rangefinder as a whole, and hard rubber covers protect the laser aperture and eyepiece.
Q: What are some key advantages of the Sightlok RF-1 vs the Tango Fire4000?
A:
Quick Detach to range objects you don’t want to point your muzzle at
Keep rangefinder warm in your pocket until needed to avoid cold weather failures
Use superior handheld lasers with superior ballistic software
Roughly $1000 cheaper
Q: What about recoil? Can’t it damage my rangefinder?
A: 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. The RF-1 spreads recoil so evenly that no spot on your rangefinder takes more pressure than your thumb puts on 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 our full analysis of the recoil question and watch recoil test videos.
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. The 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?
The RF-1 spreads recoil so evenly that no spot on your rangefinder takes more pressure than your thumb puts on 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:
Q: What about the rangefinder remote? Don’t I lose that feature with the Sightlok RF-1?
A: Yes, you do lose that feature. The Tango Fire4000 has a wired remote. A Sightlok RF-1 setup typically does not have one (unless you are using a rangefinder with a wired remote like the LE032). This means rather than triggering your rangefinder with your right hand by pressing a remote switch near the trigger, you typically mount your rangefinder on the left or top of your scope, and press the range button with your left hand while holding your rifle with your right. This works fine if you shoot off a tripod, bipod, bag, etc., but it’s a disadvantage if you shoot with nothing to support your rifle except your left arm.
Q: What about weight? Does the Sightlok RF-1 solution weigh more?
A: Yes, slightly. The Sightlok RF-1 solution weighs about 3.2 oz more.
| Part | Tango Fire4000 | Sig KILO2200 + Sightlok RF-1 |
|---|---|---|
| Rangefinder | About 14.8 oz (420 g) for the whole unit, which mounts directly to a Picatinny rail | Sig Sauer KILO2200: 7.5 oz |
| Rangefinder mount | Sightlok RF-1: 7 oz | |
| Quick-detach kit | Not needed | Sightlok QD accessory: about 0.9 oz |
| Protective cover | Not needed | Sightlok polymer protective cover: about 2.6 oz |
| Total | About 14.8 oz | About 18 oz |
| Difference | The Sig KILO2200 + Sightlok RF-1 weighs about 3.2 oz more | |
You carry an extra 3.2 ounces, but reap the massive benefit of lower beam divergence from almost any decent handheld, which is a game-changer when it comes down to ranging a target in brush. The tradeoff is easily worth it.
Q: What about the Tango Fire4000 vs the Vortex Impact 4000?
A: We think the Tango Fire4000 is the better of the two. The Vortex Impact 4000’s Bluetooth remote drains your batteries or makes you wait for it to re-pair, and the Tango Fire4000’s wired remote has neither problem. Neither would be a top recommendation. Read our report on the Vortex Impact 4000.
👉 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 actually range? · If I don’t already own a good handheld rangefinder, which one should I use with the Sightlok RF-1? · 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 the Sig KILO2200 and the Tango Fire4000:
| 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 Excessive Beam Divergence and Diagonal Beam Pattern 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.
Visual Proof of the Problem
This night vision photo shows the Vortex Impact 4000’s 45° slash beam pattern. 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.
Numerical Proof of the Problem
Here’s how the Vortex Impact 4000’s beam divergence compares with three Sig handheld rangefinders:
| Rangefinder | Beam divergence | Beam pattern | Widest beam spread at 500 yards |
|---|---|---|---|
| Tango Fire4000 | Not published | Field reports describe excessive beam divergence and a diagonal beam pattern | Not published |
| Vortex Impact 4000 | 2.0 x 0.2 MRAD | “Slash-shaped,” canted 45° | 36 inches |
| Sig KILO2200 | 1.4 MRAD | Round (30% narrower) | 25 inches |
| Sig KILO5K | 1.3 MRAD | Round (35% narrower) | 23 inches |
| Sig KILO8K-ABS | 1.2 x 0.25 MRAD | Rectangular, wider than tall (40% narrower) | 22 inches |
Result of the Problem
Due to the excessive beam divergence, the beam hits more branches, grass and ground around the target, resulting in more false or blended readings than you’d find with better quality, lower beam divergence rangefinders.
4. The Tango Fire4000 Continuous Ranging Bug Can Stop Your Firing Solution From Updating
Owners first reported the continuous ranging bug on Snipershide. The bug can start when you hold down the remote button 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, which can obviously lead to wildly inaccurate shots.
5. The Tango Fire4000 Inclinometer Bug Can Cause the Ballistic Calculator to 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. He dismissed the inclinometer bug as a nothingburger and ignored the continuous ranging bug entirely. Tango Innovations still hasn’t announced a fix or a date for one. Either bug can lead to a wrong firing solution, so Tango Innovations should acknowledge both bugs and issue firmware fixes, if that’s even possible. 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. Who Is Behind the Tango Fire4000, and Why It Matters When You Need Support
The Tango Fire4000 is made in China. That’s not the problem. Plenty of products from U.S. companies are made in China. The problem is that the company behind the Tango Fire4000 doesn’t appear to support its product or its customers, and that’s a real concern when you’re spending $1,500.
We suspect Tango Innovations is basically the U.S. sales office for Henrich Technology, a Chinese company. Here’s why:
- Tango Innovations says it doesn’t know why the environmental sensors were left out of the Tango Fire4000, suggesting that the product was designed in China (see problem 1).
- Henrich Technology filed the FCC application for the Tango Fire4000, which points to Henrich as the manufacturer. A reader points this out in the comments below.
- The Tango Innovations rep on Snipershide writes like a non-native English speaker, which suggests he may be a Henrich Technology employee. He also takes a very different approach to support than the Snipershide reps from U.S. companies like Vortex, which makes the Vortex Impact 4000. He dismissed or ignored 2 out of the 2 serious bug reports we’ve personally seen online, though those 2 instances don’t prove he responds that way to every bug report.
- Tango Innovations apparently doesn’t issue firmware fixes. That’s atypical of U.S. companies, even U.S. companies that manufacture in China.
- Tango Innovations’ customer service seems to reflect the “customer is always wrong” attitude, which is not uncommon in Chinese corporate culture.
So when something goes wrong with your Tango Fire4000, it’s probably safe to assume you’re dealing with a Chinese company and Chinese corporate culture, not a U.S. company with the kind of support U.S. buyers expect. You have a right to know all this.
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.”
The Support You Can Expect From Sightlok and Sig Sauer
Sig Sauer, by contrast, backs its electro-optics with the Infinite Guarantee™, a fully transferable lifetime warranty.
Sig is incredible with support for electro-optics. If you have a problem with their rangefinders for example, you send yours in to them and they literally just send you a new one. This is a far cry from the kind of support you receive from Henrich/Tango & Co.
And as far as after-sales support goes with Sightlok, like Sig, we have an iron-clad guarantee on our product and we are an American company with American customer support agents and American engineering experts on hand to support our customers. The Sightlok RF-1 is engineered to survive military-level engagements. Put simply, should a problem arise, you’re in better hands with Sightlok and Sig Sauer than you are with Tango Innovations, and that’s particularly important when the price tag is $1,500.
What Does a Sightlok RF-1 Setup Cost Compared With the Tango Fire4000?
| Part | Tango Fire4000 | Sig KILO2200 + Sightlok RF-1 |
|---|---|---|
| Rangefinder | $1,500 for the whole unit | Sig Sauer KILO2200: $130 |
| Rangefinder mount | Sightlok RF-1: $200 | |
| Quick-detach kit | Not needed | Sightlok QD accessory: $90 |
| Protective cover | Not needed | Sightlok polymer protective cover: $70 |
| Total | $1,500 | $490 |
| Difference | The Sig KILO2200 + Sightlok RF-1 costs $1,010 less | |
The KILO2200 has no environmental sensors. For built-in sensors, choose a Sig KILO3K or higher.
What Does a Setup With Built-In Environmental Sensors Cost?
| Part | Tango Fire4000 | Sig KILO3K + Sightlok RF-1 |
|---|---|---|
| Rangefinder | $1,500 for the whole unit, with no environmental sensors | Sig Sauer KILO3K: $275, with built-in temperature, pressure and humidity sensors |
| Rangefinder mount | Sightlok RF-1: $200 | |
| Quick-detach kit | Not needed | Sightlok QD accessory: $90 |
| Protective cover | Not needed | Sightlok polymer protective cover: $70 |
| Total | $1,500 | $635 |
| Difference | The Sig KILO3K + Sightlok RF-1 costs $865 less | |
If you already own a decent handheld rangefinder, you only buy the Sightlok RF-1, QD accessory and cover, $360 in all, and pay $1,140 less than the Tango Fire4000. The cheaper option is also the better one.
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 lower beam divergence than the Tango Fire4000 from almost any decent handheld, like the $130 Sig KILO2200
- Quickly detach the RF-1 from the rail when you want to range a target you don’t want to point your muzzle at, and reattach when you’re done, while maintaining an accurate co-witness between your rangefinder and scope
See how to turn the rangefinder you already own into a better WMLRF than the Tango Fire4000
Is the Tango Fire4000 worth it?
How far can the Tango Fire4000 actually range?
Much less than its rated 4,000 yards. See problem 2 for real-world ranging figures.
If I don’t already own a good handheld rangefinder, which one should I use with the Sightlok RF-1?
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 lower beam divergence. 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.
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. We help you find gear that fits your needs and 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!