Watch App: Ballistics

This is the support thread for Ballistics app. Please add feature requests, questions, comments here and I'll do my best to answer them :)

Download the app here

Ballistics is a ballistic calculator. It's a perfect companion for hunters and long range shooters who occasionally need to accurately hit a target at a different range to what the rifle has been zeroed to. Distance to target can be set directly on the main screen with up and down buttons and the results can be read on the same screen when the calculation completes.

After installing the application you need to go over the settings in Garmin Connect mobile app and change the defaults to match your set up. Sight settings allow setting up all rifle related parameters: sight height from bore centerline, the range you've zeroed your rifle to and how many Minutes of Angle (MOA) each click on your scope is. Cartridge and bullet related settings also need to be configured before use. Drag function and drag coefficient depend mainly on the shape of the bullet you're using, this data can probably be found in the bullet manufacturer's data sheet (example from Lapua can be found here). The initial velocity is the speed the bullet leaves the barrel and can be found in the cartridge data sheet if you use factory-made cartridges (example from Lapua can be found here).

On first run and after changing rifle or cartridge related settings the app will pre-calculate some values which will take a while, even couple of minutes (a text "Initializing rifle" is displayed). The ballistics calculations itself can take some time (the more further the target, the more time it takes to calculate the result), but not as long as the initialization.

Quick start up guide

- on main screen "up" and "menu" buttons open main menu where all parameters are set. The "start/stop" button begins the calculations and eventually opens the result screen. On result screen only "back" button is active

- to set the cartridge properties open Garmin Connect on your mobile phone, go to Ballistics app info page (Garmin Devices / Device / Connect IQ Apps / Ballistics) and select Settings. Values are inputted in statute units, but displayed in the app in the unit of your preference.

Disclaimer: the application uses generic ballistics formulae which should be accurate enough for hunting use. For shots longer than 250m (or 270yds) the calculations should be verified at shooting range to make sure the calculated values match your specific cartridge and gun combination.

Known issues in latest version

- No known issues

Version info

1.39, 2015-11-14
- Added support for Fenix 3, D2 Bravo and Vivoactive (not tested with real devices though)
- Numeric inputs are now native
- Cartridge and sight settings are now managed in Garmin Connect (statute values)
- Settings can be viewed in the app (Menu -> Other). The setting list is scrollable.
- Results are adjusted by temperature, altitude and pressure values read from the sensors (can be turned off in the app settings)
- Added support for 0.1mil and 0.2mil scopes
- Smaller memory footprint

1.1, 2015-07-06
- Values can be now set a bit faster by long-pressing up (menu on Epix) or down (clock on Epix) buttons. This changes the values 10x.

1.0, 2015-06-29

- new look & feel

- optimized performance

- now indicates when calculating with a progress bar

- re-added windage/drift calculation

0.92R beta, 2015-04-26

- Reduced feature set version to fix memory issues (app not starting). No windage support.

- Missing features will be added once memory issues are fixed

0.91 beta, 2015-03-29

- Removed unused menu item

0.9 beta, 2015-03-29

- Initial upload. Not tested with real hardware.

Donate here

Former Member over 9 years ago

A more efficient way to enter values with large numbers?

Could it be possible to set up an easier UI for entering large numbers ie "Initial Velocity".

Making a way to enter large number values with the touch screen would be awesome.

The "Initializing Rifle, Calculating Ballistics" part takes 3 minutes to calculate...thats a bit long for my taste. Is there anyway to speed those calculations up?

PS. The app on the epix is working 90% better than it did before your last update. Fantastic progress.

mikkosh over 9 years ago

Could it be possible to set up an easier UI for entering large numbers ie "Initial Velocity".

Making a way to enter large number values with the touch screen would be awesome.

I am waiting for Garmin to improve the way numbers are input (there's no generic number input, but I'd imagine it would appear there someday). There's an undocumented trick though that might be of help: when inputting numbers/angle etc if you "long press" the up-button, the number increases in greater increments (how much depends on what value is in question).

The "Initializing Rifle, Calculating Ballistics" part takes 3 minutes to calculate...thats a bit long for my taste. Is there anyway to speed those calculations up?

Unfortunately not, at least without a precision trade off.

The Initalization takes the longest time. Basically the application is then calculating the angle between your bore and sight required to hit the target at zero range. Once the value is calculated the zero angle is cached and is needed to be calculated again only when you change either gun or bullet properties. The calculations are done with a solver which basically tries various angles until the bullet hits the target.

Once the zero is resolved and cached, the calculations itself are done with "3rd degree of freedom" analysis. It takes various parameters into account and should be quite accurate. The calculation routines are somewhat based (but heavily refactored) on GNU ballistics.

PS. The app on the epix is working 90% better than it did before your last update. Fantastic progress.

Thanks for the feedback. Make sure to add a positive review to the app page as well so that other users also know that the app is now working ;)

Former Member over 9 years ago

Thanks for the feedback. Make sure to add a positive review to the app page as well so that other users also know that the app is now working ;)

Done, and donated. Will donate more on next major update.

.... if you "long press" the up-button, the number increases in greater increments (how much depends on what value is in question).

Unfortunately when you long-press "down" it is a hotkey for the "clock" on the epix :( ....you sure there isnt a better UI for large number inputs?; Maybe similar to the UI on the "Timer" function on the epix? Menu> Clock > Timer

Former Member over 9 years ago

Temperature Data?

Temperature needs to be added to make this app. Its a pretty important variable.

Its 90+ degrees where I am at the moment, and that makes a difference on shots out past 700y.

mikkosh over 9 years ago

Thanks for the donation Kumosan :)

Yup, the long-press-up is basically a hack – and since I can't do the same with down button it's also quite inconvenient one (although the numbers rotate to minimum once they reach the defined max value). Unfortunately the device does not have enough memory for me to build more sophisticated inputs to replace the current generic one. The app is now running close to devices memory limit and adding more ui components would surely push it over the limit. Best option would be to have a flexible number input as a part of the CIQ platform.

Adding the temperature and atmospheric correction to ballistic coefficient should be simple enough. Although I probably cannot make them as user inputted value due to memory restrictions, but could read them directly from the device's sensors. Would this help? The temp correction would naturally not correct the changes the temperature has to the initial velocity.

By the way: If anyone wishes to try the app on other Connect IQ supported devices, PM me and I'll compile a sideloadable version for you. The 1.0 version does not support touch screen, so physical buttons are a must.

Former Member over 9 years ago

You should be able to process held key behavior for the Down key on both the Epix and Fenix. To do so, you will need to capture the Clock key event, and return true to prevent the default system behavior from triggering.

mikkosh over 9 years ago

Thanks Brian, added support for capturing the clock event and just released 1.1 a second ago :) Long-pressing either up (menu) or down (clock) changes the value 10x more than just normally pressing the corresponding buttons.

Former Member over 9 years ago

Thanks Brian, added support for capturing the clock event and just released 1.1 a second ago :) Long-pressing either up (menu) or down (clock) changes the value 10x more than just normally pressing the corresponding buttons.

Very nice!

Thanks for the donation Kumosan :)

Adding the temperature and atmospheric correction to ballistic coefficient should be simple enough. Although I probably cannot make them as user inputted value due to memory restrictions, but could read them directly from the device's sensors. Would this help?

Absolutely, that would help! Also, Including the Altitude within the calculations similar to this device would be very pro. Your app would essentially make the epix one of the best ballistics tools in the world especially since it would effectively take the temp and altitude data directly from the watch!

Expect another donation from me if you can make the above happen. And to be honest, if Garmin allows it at the moment, especially if I were you id really consider making this a paid app, if you were able to include all of the above.

Former Member over 9 years ago

+1 on Fenix 3 support!

Former Member over 9 years ago

support fenix 3

please support ballistics app for fenix 3