User Guide & FAQ

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Download “Ballistic: Understanding the Basics

Quick Tips and Hints for using Ballistic

  • Ballistic has many different settings including full metric support. Tap on Apple’s “Settings” icon, then scroll down. You should see Ballistic near the bottom. Tap on it to bring up the application’s settings.
  • Ballistic has three ballistics libraries: a projectile library, a loads library, and a custom library. Advanced and iPad editions also include Litz library. The projectiles library (and Litz library) is based on bullet diameter – not caliber, so remember that .223/5.56 projectiles are actually .224, .50 BMG is actually .51, and so on. Labels have been added to provide hints to popular bullet calibers, as shown in the screenshots. The loads library is based on caliber, and so you’ll want to select the exact type of ammunition for your rifle. You’ll find metric loads near the bottom. The library fills in the fields for ballistic coefficient(s), bullet weight, diameter, drag function, and (loads only) muzzle velocity. If you’re using the projectiles library, you’ll need to supply the correct muzzle velocity corresponding to your ammunition. This is commonly found on the box or on the manufacturer’s website or your reloading manual. Even though this information is provided for you, it’s still a good idea to verify the data in the library with the information from the manufacturer. Please email us if there are any errors in either library (include the correct info and cite the source).
  • In the range log, double-tap the target to slide it to the bottom of the screen, increasing the size of the impact table. Tap the Target button to change the target. Double tap on an impact marker (the bullet hole) to toggle it between standard (black) and cold barrel (blue). Tap on an impact record in the impact table to bring up an action sheet with options. It’s a good idea to record your cold barrel shots, so that you can run a cold barrel report at some point to get an idea of how your rifle shoots cold.
  • Wind angles work like this: 0° = headwind, 90° = crosswind (left to right), -90° = crosswind (right to left). You can use any angle, of course, not just these. You can also enter input in O’Clock format; e.g. 3:00 will automatically translate to 90°. Velocity will automatically be adjusted to account for the appropriate headwind calculation. To use O’Clock format in the HUD, set the windage dial format in Settings. The default wind input value is the wind direction (e.g. which way the wind is blowing). You can change this to wind origin in settings, if that’s what you’re used to.
  • Snap a screenshot of your Target Data card by pressing Home + Power together, then import it using the Image Capture Utility. To save a ballistics chart to your photo album, press Options followed by Save Chart. You can then use Apple’s Image Capture Utility to import your photo library onto your Mac.
  • If you are zeroed in yards, but want distances in meters (or vice-versa), create a favorite containing your zero in the units you originally used. Switch over to the units you want your distance measured in by changing the global “Distance Units” setting. When you load back the favorite, your zero range will be automatically converted (e.g. 300 yards zero = 274.32 meters), and your output will be set for whatever unit of measurement you’re currently using.
  • The “Desired Accuracy” GPS setting allows you to set the level of accuracy you’re willing to settle for. As Core Location attempts to get a fix, its increasing level of accuracy will be reported back to the application. The higher you set the desired accuracy, the longer it will take for Core Location to get the fix you want. If the GPS can’t give you the desired accuracy within the timeout period you specify, Ballistic will use the best fix it could obtain. This is only particularly important when calculating altitude, as your geographical coordinates only need to get you to the nearest weather observation. We currently have the settings tuned as follows: Best – Altitude within 30 meters, Good – Altitude within 150 meters, Fair – Altitude within 300 meters.
  • If you previously used the One-Touch Range Notes to fill in your current location, you can tap the “Location” cell to launch the Maps application with the current coordinates filled in. This is useful for finding that same hunting spot again. It also works if you just type in the location as an address or other place that Maps can identify, but using the one-touch feature will give you exact coordinates.
  • You can turn the “Wind Drift Chart” into a “Spin Drift Chart”. Do this by setting the wind speed to zero, then load your favorites for comparison.
  • When entering Density / Mach data, you may enter the temperature in the Mach field and Ballistic will automatically calculate the speed of sound at this temperature.
  • The yellow band in the trajectory output indicates the sound barrier; it’s where your bullet falls from supersonic into subsonic. This is typically where your bullet can begin to tumble.
  • The red arrows indicate your point blank range, based on your vital zone radius. For your current zero, you can shoot within these ranges and be +/- your radius without any scope adjustments.


Do you plan to make Ballistic available on Android / Blackberry / Windows / etc?
We don’t have any current plans to expand Ballistic beyond iOS. Sorry.

Will this run on my (Dell Axiom, Windows Phone, Newton Message Pad) non-iOS device?
Ballistic ONLY runs on iOS devices. This includes iPhone, iPod Touch, and iPad. Ballistic will NOT run on PocketPC devices, Windows phones, Android phones, or anything that is not running Apple’s iOS operating system. Sorry.

Does the ballistics library have my favorite brand?
Ballistic includes a library of over 5,400 projectiles, factory loads, military loads, and professional measurements. The library is always growing, but if you can’t find your favorite brand, you may input your load’s ballistic coefficient and muzzle velocity manually. This information can usually be found on the manufacturer’s website or by calling them. If your favorite manufacturer publishes their ballistic coefficients (and muzzle velocities, if they’re loads), send us link and we’ll try to add it to our database.

Does the ballistics engine work without cellular coverage?
Yes. The ballistics engine is compiled into the application so it does not need Internet access. You can even perform calculations on your iPod touch with no Internet. What you will need Internet access for, however, is if you want to download up-to-date weather station information from a weather service. Don’t worry, though, you can always enter it in manually if you’re shooting in an area with no coverage.

What is your relationship with the author of JBM Ballistics?
We licensed the JBM ballistics engine after using it extensively for years. We initially designed this app for ourselves (after wasting money on other ballistics calculators in the App Store, only to be disappointed), and wanted the most powerful and accurate ballistics engine powering it. Even though the app uses the JBM ballistics engine, please make sure to contact us directly for support as JBM won’t be able to help answer your questions. Thanks.

Are your calculations the same as everyone else’s?
Most ballistics computers (including Ballistic) use well established mathematical formulas used for over one hundred years. The mathematics were well documented by Sierra’s ballistics laboratory, based on calculations used by the US Army Ballistic Research Laboratories at Aberdeen Proving Grounds. These calculations are used in Ballistic as well. 3-DOF calculations for trajectory, atmospheric correction, etc., are typically very similar between software packages, and should provide similar results.

While all results are similar, precision is pretty important when it comes to a good ballistics calculator. That’s the main reason Ballistic now uses the acclaimed JBM ballistics engine and why we decided not to use one of the free but much less accurate and less feature rich open source libraries (like the one that the Direkon engine is based on). One area where Ballistic is more accurate than many is in its ability to account for a number of advanced factors, such as gyroscopic spin drift, Coriolis acceleration, atmospheric zero conditions, and in its ability to handle things like stepped ballistic coefficients (such as those published by Sierra) and complex wind configurations. Support for these is very important, as it allows Ballistic to fine-tune its physics to your environment, to give you results that work in the field, as opposed to in a lab. Ballistic is also capable of handling G1-G8 drag models, allowing for more accurate results when calculating bullets such as spire points, VLDs, and military bullets. Don’t settle for a ballistics program that handles only G1 – it was made for bullets that existed over a hundred years ago and doesn’t accurately calculate today’s more flat-base projectiles. The projectile library contains G7 and G8 data for all its military projectiles rated at Aberdeen Proving Grounds and can handle any G1-G8 coefficient you provide. It can also perform real-time conversions between drag models if you’d like to convert a commercial coefficient to a more suitable one. Finally, if you’re looking to squeeze every last bit of accuracy out of your rifle, Ballistic includes a library of Bryan Litz’ G7 BCs for many popular projectiles, which more closely reflect the actual accuracy of a bullet, rather than its advertised accuracy.

With that said, the JBM ballistics engine is far superior to its competitors in that, in addition to basic 3-DOF calculations, JBM’s sophisticated engine is capable of accounting for advanced calculations including linear wind calculations (and calculations from more than one wind zone), better atmospheric density equations, and incorporates more advanced physics in its computer. If Ballistic can get even a couple inches higher at 1,000 yards, then that’s significant in real-life application. Rather than trust some home grown ballistics engine to be written correctly, trust one that’s already used by top shooters. Nearly every application out there measures their accuracy based on how close it comes to JBM… so why not just use an application that runs the JBM engine?

How do I add a favorite?
First, calculate a trajectory. When the trajectory results appear, tap the plus sign on the upper-right of the screen to add it as a favorite.

Where can I find the settings?
You can access them by going to the Settings app on your iPhone or iPad:
Scroll to the bottom. If you didn’t know that, you might be pleasantly surprised to find that many of your other installed applications may also have a section at the bottom.

How can I get tenths or hundredths in the HUD?
Go into the Settings app on your phone, scroll down to select Ballistic, then change the “Output Precision” in the “Head-Up Display” section from “Whole Number” to either “Tenths” or “Hundredths”.
I change the settings, but the app still uses my old settings.
Most settings can be changed without restarting Ballistic, but some do require that you restart it. To force-quit Ballistic, go to the home screen. Double tap the home button, swipe left until you see Ballistic, then flick it upwards like you’re trying to flick it off the screen which will exit the app. You can also simply restart your phone. This can also occur if you’ve set application defaults. For example, if you’ve changed your default atmosphere type to use Density Altitude, but are still seeing meteorological fields, you likely saved the meteorological data with your defaults. Tap on the action icon and “Reset Defaults” after you’ve made such changes, and this should update your data input.

Can I Enter Density Altitude or Density of Air?
Yes! You can change your atmosphere format to either of these. Go into Settings, and then select the Atmosphere option.
NOTE: If you saved custom defaults, or are using ‘Save State’, you’ll need to ‘Reset Defaults’ after you change default atmospheres. Otherwise, the old atmosphere from the default will be loaded.

How can I set new application defaults?
Tap on the action icon in the upper-left hand corner of the Trajectory screen, and select “Save Defaults”. Whatever values you have plugged in will become your application defaults. To reset them to factory, select “Reset Defaults”. You can also turn on auto-save to save your last calculation.

How can I compare Ballistic with other programs?
When comparing Ballistic to something else, keep in mind that many packages use different defaults or even different atmospheric measurements, so you might need to do some tweaking to compare apples to apples. Make sure both packages are set to the same zero, sight height, and especially the same atmosphere. Ballistic uses the ICAO atmospheric model, while others (such as Perry-Systems’ ExBal) use the US Army standard. Be sure to enter one or the other pressure manually into both packages to compare apples to apples. The default atmosphere used by Ballistic is sea level with 29.92 Hg., 59 °F, 78% humidity. Be sure your comparison calculations match these (some packages use 0% humidity, or other default values). Finally, enter ballistic coefficients by hand rather than relying on each package’s library for your testing, as they might each use different values.

You should be able to successfully compare Ballistic to JBM and get identical results. Do this by starting with Ballistic’s factory defaults (use “Reset Defaults” if necessary). Now, set a muzzle velocity of 3000 fps, then create a constant, 10mph wind stretched from 0-1000 yards (or “muzzle”, if using simple wind), 90 degrees. These settings should perfectly match JBM’s defaults and give you 294.6″ of drop at 1000 yards, and 82.6″ of wind drift.

Should I mount my iPhone/iPod on my rifle?
If you want… but not without a military-approved recoil-proof mount. The iPhone is not recoil rated in and of itself, so unless your manufacturer is going to guarantee that the device will not be damaged, and is willing to back up that claim by buying you a new one, you could cause irreparable damage to the device. Unless you have such a guaranteed mount, we recommend that you remove your iPhone or iPod from the rifle before actually firing. We’ve busted “military grade” scopes, levels, lasers, and other equipment from the recoil on our rifles – don’t take the amount of force for granted; it can damage your iPhone without a properly designed case.

How can I calculate drop from barrel, rather than from a zero?
Set both your “Sight Height” and “Zero Range” to zero values.

Why did you write this?
As avid shooters, we got sick of printing and memorizing trajectory cards for every load we fired. The iPhone is the ideal device for calculating real-time ballistics given its GPS, accelerometer, and network connectivity. We wanted a tool that could immediately adjust our calculations for the current weather conditions, altitude we were shooting at, and convert between yards/meters depending on what range we were using. We gave a different iPhone application a try and decided that iPhone users deserved better. It works well and we take pride in making Ballistic the best mobile ballistics computer on the market, if anything for our own personal enjoyment.