The TruFlite ballistic calculator is a tool that turns your Garmin watch into a compact and easy to use ballistic calculator. It is basic, and you might not always yield a first-round hit at 1,000 meters, but it will get you close enough to make the necessary adjustments for a successful second round hit.
Apps like Strelok pro might give you more accurate results, but fidgeting with a two thousand dollar smartphone with dirty fingers in the field is a pain in the ass to be sure. With TruFlite, you are able to set the distance and get an instant firing solution with the press of a button.
What data does the TruFlite Ballistic calculator take into account?
The TruFlite ballistic calculator uses the same data that most other more advanced ballistic calculators use. Some of this data is automatically measured and accounted for and others require manual input. You do need to input some data while setting up the calculator, but the setup only needs to be done once.
Shooting data measured automatically by the watches sensors:
- Barometric pressure
- Altitude
- Temperature – It is recommended that you use an external thermometer because your body temperature can distort the reading given by the watch.
Shooting data entered manually by the user:
- Distance to target – preferably determined with a laser range finder.
- Ambient temperature – You can let the app get this from the watches sensors, however, you’ll get more a more accurate reading using an external thermometer.
- Crosswind – Either by estimating or by using a kestrel or similar weather device.
Data entered in manually in set up:
- Ballistic Coefficient – This is obtained from the manufacturer of the bullet being used.
- Muzzle velocity – You can get this from the bullet manufacturer, however, it is better to measure it using a chronograph.
- Zero Range – This is the distance at which you sighted or zeroed in your rifle.
- Sight Height – This is the distance from the center of your barrel to the center of the rifle scope.
Does the TruFlite ballistic calculator account for spindrift?
The TruFlite ballistic calculator does not account for spindrift, but that is no reason to give this app a miss. Spindrift accounts for only a tiny part of the firing solution, about 15cm at 1,000 meters (or 6 inches at 1,000 yards). All you need to do is make a range card with spindrift adjustments at 100m intervals and add the relevant adjustment to your firing solution. Use an app such a Strelok PRO to build this list and keep it with you when you are in the field.
Does the TruFlite ballistic calculator account for relative humidity?
The app also does not take humidity into account either, however, I ran the figures through Strelok PRO to see what the difference is between 90% and 5% humidity at 1,000 meters. The results showed me that it really isn’t enough of a difference to be a problem.
| Humidity | 90% | 5% |
| Elevation Adjustment: | 12.0 MRAD | 12.1 MRAD |
| Windage Adjsutment: | 0.3 MRAD | 0.4 MRAD |
A difference of 85% in humidity as in the example above is the worst-case scenario, and in reality, you’d only have a difference of half that at worst. At 1,000 meters, you’d have to add 0.1 MRAD to elevation and windage. Half of that is less than one click on most modern rifle scopes and for most people, is not even worth adjusting for.
With that in mind, I am pretty comfortable with the results from the TruFlite ballistic calculator, even though it doesn’t account for relative humidity.
How Accurate is TruFlite ballistic calculator for Garmin?
The TruFlite ballistic calculator for Garmin is accurate enough for most precision shooters. I ran the TruFlite ballistic calculator side by side with Strolok PRO, an app that I have used for years. I have found the firing solutions to be almost identical on both platforms.
I found that it will never be out by more than 0.1 MRAD for spindrift and relative humidity. If you would like to account for these, I recommend that you simply print a sheet with adjustments for every 100m intervals. You can then just add them to your adjustments that you get from the TruFlite ballistic calculator.
Conclusion
While Garmin watches are expensive, the TruFlite ballistic calculator is completely free. If you are in the market for a watch that has a ballistic calculator, then this might be an option for you. It will give you results accurate enough for most shooters, rifles, and environments. It is incredibly convenient to use in the field.
Have you used this ballistic calculator? Do you use Garmin watches? What are your thoughts? Let me know if the comments below, I’d love to hear your opinion.