Last updated April 18, 2012

About Ballistic

• Fully integrated split-screen ballistics, favorites, and range log
• Automatically updates ballistics calculations as you edit
• Full screen, hi-resolution charts!
• Rotate in any orientation
• Larger target sizes in range log
• Even more features in the works

Ballistic Features

• An Expansive Ballistics Library
  Select from a library of over 3,500 projectiles and factory loads from leading manufacturers, military projectiles, or specify your own projectile properties. Library includes the latest 2011 commercial data and G7 military coefficients from Aberdeen Proving Grounds. Just select your bullet diameter and all of the available projectiles will appear, sorted by manufacturer. Auto-select the best factory load by wind drift, energy, or flatness. Ideal whether at the range, or comparing boxes of ammunition at the store.
  
  New! Now includes air rifle loads!
  
  Click here for a list of supported loads, projectiles, and manufacturers
  
  
• JBM Ballistics Computer
  The JBM Ballistics computer, written by James B. Millard, is among the world's finest ballistic engines in existence. Used by competition shooters, hunters, and the military, this powerful ballistics library delivers precision results. Results is what it's really about, isn't it? The JBM engine also adds new features such as velocity adjustments for chronograph, optimum point blank range, upwind (z-wind) correction, and midrange/downrange wind sources. When other ballistics applications look to measure their accuracy, they use the JBM engine as their gold standard.
  NOTE: The original engine used in earlier versions of Ballistic is also available as an option.
  
  In addition to the JBM ballistics engine, Ballistic now also calculates gyroscopic spin drift, Coriolis acceleration, and Miller bullet stability. Bullet stability helps you determine if your barrel twist can support a projectile at a given velocity.
  
  
• One-Touch Atmosphere(TM) (Core Location)
  Correct your calculations for the current atmosphere by pressing the Core Location button. Your altitude, standard pressure, temperature, relative humidity, and wind velocity will be automatically set based on your current location and information from the NOAA National Weather Service or GeoNames. A global setting allows you to set which fields are updated. Manual entry can also be made.
  
  When calculating Coriolis acceleration, the iPhone 3GS' built-in compass can automatically acquire your Azimuth to accurately calculate the correct adjustments for both windage and elevation.
  
  
• New! Printing Support!
  Print trajectory cards or ballistics charts straight from your iDevice!
  
  
• Bookmarks and Save State
  Bookmark your favorite calculations and recall them later, or load them back into the ballistics calculator to tweak them or generate charts. Add notes to your bookmark to display underneath the bookmark title. Your bookmark will retain your ballistics information, zero, atmosphere, range, and all other data from your calculation.
  
  In addition to bookmarks, Ballistic can be configured to automatically save the last calculation in its active editor, and recall it the next time you start the application. Or leave auto-save turned off, and tweak the default values you'd like loaded whenever you use the application, such as zero range, wind velocity, and everything else.
  
  
• Angle Acquisition
  Aim the iPhone at the target like a remote control, then press the LOS Angle table cell. After a three-second countdown, the table cell will be updated with the correct shooting angle to the target based on the accelerometer reading. A preview label displays the angle prior to capturing it. The angle can also be inverted by 90° making it suitable for use in a weapons mount. The HUD (Field Tactical Edition only) automatically locks onto your current angle and updates your calculations every second.
  
  
• Ballistics Charts
  Ballistics charts allow you to display the energy, velocity, and drop for your current projectile, or compare up to eight projectiles together on the same screen. Your current atmosphere and zero are automatically applied to all projectiles, so you're comaring apples to apples. Compare bullet path and energy or wind drift. Ballistic will also show you trajectory charts based on altitude or shooting angle. Zoom up to 300% or save a full size chart to your photo library and transfer it to your desktop, or send a full size chart in an email.
  [ example 1 | example 2 ]
  
  
• Variable (Stepped) Ballistic Coefficients
  Support for variable (stepped) ballistic coefficients for many popular projectiles including Sierra MatchKing®, GameKing®, and ProHunter®. Variable coefficients allow for more precise calculations and overall better accuracy by adjusting the bullet's flight to fit the commercial G1 drag model. Ballistic also supports all G1-G8 drag models.
  
  
• Automatic Drag Model Conversions
  Automatically convert between two different drag models. Ballistic will recalculate the ballistic coefficient and adjust its trajectory to fit the new drag model. This is ideal if you only have a G1 coefficient for a VLD, spire point, or other type of uniquely-shaped projectile, as it allows you to apply a more accurate drag calculation. This may improve your long range accuracy beyond that of the standard G1 calculation provided by the manufacturer. Wish your manufacturer produced stepped BCs? Convert the drag model to apply a more suitable drag.
  
  
• Minimum, Maximum, and Optimum Point Blank Range
  Ballistic automatically calculates your minimum and maximum point blank ranges based on your zero and the vital zone radius you specify, and will display these in the form of red arrows. The JBM engine can also calculate your optimum point blank range and will display this in each calculation. In addition to this, the sonic boundary will be marked with a yellow line.
  
  
• Full Metric Support
  Global settings exist to change the units of measurement for distance, atmosphere, and all other units. This includes bullet drop, altitude, sight height, wind speed, temperature, pressure, velocity, and energy. Favorites are automatically converted so that you can retain your zero and atmosphere, but appply the same calculations to either yards or meters. In other words, your favorite will stay zeroed at X yards, and give you accurate output for Y meters, and vice-versa.
  
  Elevation and windage output can also be specified in In, Cm, MOA, IPHY (Inches per 100Y), 1/8 Minute Clicks, 1/4 Minute Clicks, 1/2 Minute Clicks, and 1 Minute Clicks, mRad (MIL), .1 mRad, .2 mRad, .5 mRad, Cm/100M, and 1/2Cm/100M. A custom click value can also be provided for scopes with nonstandard MOA click values. When in metric mode, the inches column automatically changes to centimeres. A global preference selects between USMC and Army Mil-Dot specs.
  
  
• Mil-Dot and MOA Distance Estimator
  Calculate distance using Mil-Dot or MOA reticles. Supports conversions including inches, cm, feet, yards, and meters. Supports both USMC and Army Mil-Dot specs.
  
  
• Range and Scoring Log with One-Touch Notes
  Range log to keep a journal of all your hunts, shoots, adjustments, points of impact, and scores. Touch the Core Location button to automatically fill in your current coordinates, which you can later recall into the Maps application. Query the NOAA National Weather Service for local atmospheric and weather conditions. Range log can automatically tally your target data cards and even keep track of your X's. Choose from a variety of targets including standard, F-Class, pistol, silhouette, archery, buck targets, and more. Different targets for zero data cards are also available. Use your zero data log enries as a source to set your calculations' zero atmosphere, or run scoring and cold barrel reports for each rifle.
  
  
• Reloading Data
  Reloaders can store their reloading information with each bookmark, including powder type and measure, COL, brass, and other information. Ballistic automatically calculates OGW (Optimal Game Weight) at both muzzle and zero, TKO (Taylor Knock-Out Factor), and IPSC Performance Factor.
  
  
• Very fast and precise calculations, even at long range
  Ballistic undergoes heavy testing and comparison with known data, and has satisfied many in accurately reflecting true-to-life trajectory. It compares very well to well respected ballistics packages such as Sierra's Infinity suite for the desktop. Whether you're using the JBM Ballistics computer or the original Ballistic engine, world-class results are what our world-class shooters are expecting - so we'd better deliver.
  
  
• Share trajectory and charts via email
  Full size trajectory results and ballistics charts can be shared via email.
  
  
• Midnight Skin
  Turn on the midnight skin if you prefer an all black theme.

Screenshots

Trajectory Data Entry Supply information about your ammunition, scope height and zero, and you're ready to go.	Ballistics Library Labels have been added to many popular bullet diameters to aid in finding your projectile.	Ballistics Library Choose from a ballistics library of over 3,100 projectiles and factory loads, including many name brands and government bullets.	Trajectory Calculation Projectiles with stepped ballistic coefficients provide for greater accuracy in your calculations. Many military projectiles use G7/G8 data documented at Aberdeen Proving Grounds.	Auto-Select Automatically select the best factory load for your rifle based on wind drift, flatness, or energy.
Ballistics Charts Generate beautiful ballistics charts with the touch of a button. Charts display drop, energy, and velocity to any valid range, with any zero, or compare drop and energy for up to eight projectiles. Converts to cm and Joules when in metric mode. Export full size charts to your photo library and sync to your desktop.	Windage Charts Compare the wind drift for up to eight projectiles on one screen. Ballistic will automatically apply your current atmosphere. Choose from favorites or use a custom / library projectile. Distance markers at every 100 yards/meters can be toggled on/off.	Chart Zoom Zoom in on charts up to 300% or save a full size image to your photo library.	Trajectory Charts Chart ten different trajectories for the same projectile for different altitudes or shooting angles. Automatically calculates how far your zero will deviate from standard.	Mil-Dot & MOA Distance Estimator If you have a Mil-Dot or MOA reticle in your scope, this simple tool estimates distance based on the size of the target and its milling size in your scope.
Favorites Store a list of favorites you can recall with a single tap. Favorites can be loaded back into the calculator to adjust for atmosphere or other changes.	Atmosphere Supply a custom zero or current atmosphere to correct your trajectory calculations. Standard pressure can automatically be calculated based on your altitude. Press the Core Location button to query the NOAA National Weather Service for the conditions based on your coordinates.	Range Log The Range Log is automatically sorted by rifle type, entered by the user. Generate cold barrel reports or scoring reports for each rifle.	Range Log Notes Record the conditions of every zero or shoot in the range log. Includes standard atmospheric fields and other notes. One-Touch can record weather, altitude, and your current location. Tap on Location to bring up the Maps application with your last coordinates.	Zero Data Zero data cards can be created within each range log entry, so you have an accurate log of every zero. Notes can be added to record the atmosphere and other variables. Use your zero data log entries as input for "Zero Atmosphere" calculations.
Target Data Target data cards can be created with each range log entry, allowing you to record your shoots or hunts. Several different target cards are available. Score tallying is automatic.	Buck Target Another example of a Target Data card in the Range Log.	Settings Set your default ranges and elevation and windage adjustments. Activate simple mode to hide more advanced options.	Settings Set your default units of measurement and Mil-Spec standard. Invert the angle of the accelerometer 90° for use with a weapons mount.	Settings Core Location settings allow you to adjust the desired accuracy you're willing to wait on Core Location for, set the weather service, GPS timeout, and set which atmosphere fields to update.

Ballistic FTE: Field Tactical Edition

HUD Display The HUD displays the range, wind velocity, and wind angle on click-wheel scroll pickers. Simply flick to the current settings and the trajectory will update. Turn on the LOS Angle switch for real-time angle locking.	HUD Settings Select a ballistics profile from the HUD Settings screen. Choose a favorite or create your own custom projectile.

Hints

• Ballistic has many different settings including full metric support. Tap on the iPhone'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 two ballistics libraries: a projectile library and a loads library. The projectiles 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 me 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 (arrow) to toggle it between standard (red or black, depending on the target type) and cold barrel (blue). Tap on an impact record in the impact table to bring up an action sheet with options.
• Wind angles work like this: 0° = headwind, 90° = crosswind (right to left), -90° = crosswind (left to right). 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.
• 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 yard zero = 274.32 meters), and your output will be set for whatever unit of measurement you're currently using.
• If you are in an area where Core Location is unable to determine your altitude frequently, Ballistic will query a toplogical service to estimate your altitude. Increasing your GPS timeout to 60 seconds (in Ballistic's global settings) will cause Ballistic to wait longer to try and acquire a real fix.
• The "Desired Accuracy" 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. I currently have the settings tuned as follows. If your'e not concerned with altitude, turning off the "Altitude / Pressure" toggle in the "Update Fields" setting will result in much quicker Core Location queries.
  • 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.
• As of version 2.0, 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.

Known Bugs

• [FTE] The HUD in version 1.6 and higher reportedly does not function with some favorites created with much older versions of the software. The simplest workaround is to simply recreate any favorites that are causing problems.

FAQ

List of Terms

• Ballistic Coefficient (BC): Typically obtained from the manufacturer, this value represents the ratio of drag for a given bullet. The ballistics library contains ballistic coefficients for over 1,500 different bullets, but if you don't find yours there, contact your manufacturer.
• Bullet Diameter: The actual diameter of the bullet in inches. Not caliber. This value is used primarily for informational purposes, but you'll need to know the correct diameter if choosing a bullet from the projectiles library. The loads library is, however, sorted by caliber, allowing you to choose your particular cartridge type without knowing the diameter.
• Bullet Weight: The weight of the bullet in grains (7000 grains is equal to one pound). This is used primarily for informational purposes, and is filled in when you select a projectile or load from the ballistics library.
• Native Drag Model: A ballistic coefficient's value is based on a specific drag model; e.g. G1, G7, etc. The drag model that goes with the supplied BC is the native drag model. Most manufacturers provide BCs with a G1 native drag model.
• Muzzle Velocity: The velocity of the bullet as it leaves the muzzle of your rifle. Most manufacturers print average velocities on their boxes, or provide this information on their website. For more accurate results, you might consider using a chronograph to measure actual velocity. Velocity can change by a number of factors including barrel length, temperature, and even the amount of fouling in your rifle barrel, so if you're serious about pin-point accuracy, you should invest in a good chronograph and practice consistent barrel cleaning after each shoot.
• Use Drag Model: If you would like to convert this projectile's BC to fit some other drag model, choose the drag model you'd like to convert it to here. The BC will be adjusted based on the drag model selected and the given muzzle velocity.
• Zero Range: The range at which the rifle is zeroed at, with the given ammunition. It is expected that the rifle's point of impact will match the rifle's line of sight at this range, at zero angle.
• Sight Height: The distance between the centerline of the barrel and the center of the scope or sight. This is very important, as the bullet's drop will begin at this distance out of the muzzle.
• LOS Angle: Line of sight angle. This is the angle at which your rifle is aimed. A value from -90 to +90 is acceptable here. The shooting angle dramatically changes the gravitational effect of the bullet, ultimately changing your trajectory. If shooting straight, leave this value at zero.
• Zero Atmosphere: The atmosphere at which you zeroed the rifle at. When this is disabled (default), no corrections are made to account for this. If you have this information available, however, it will allow you to fine-tune the output to account for zeroing in one climate and altitude (e.g. summer, at 300 ft above sea level) and shooting in another (e.g. winter, at sea level).
• Current Atmosphere: The current climate and altitude you are shooting at. Pressure, humidity, and other factors can affect the density of air, ultimately affecting the amount of drag on the bullet. By specifying a current atmosphere, Ballistic adjusts the BC of the bullet to compensate for this. Leaving this option disabled will cause Ballistic to forego any corrections.
• Pressure is Absolute: If the pressure being provided is the absolute pressure given elevation, turn this switch on. If the pressure needs to be corrected (e.g. if it is a station pressure, reported elsewhere), leave it off.
• Wind Velocity: The speed of the wind. This is used to account for windage (in crosswinds) and also adjust the bullet's velocity (in headwinds).
• Upwind Velocity: If your range has upwind flags, you can enter the estimated speed of the wind traveling upward (or downward) into this field, and your elevation will be adjusted to compensate.
• Wind Angle: The angle of the wind direction. Changing this value can affect both windage and trajectory by a factor of the wind speed.
• Wind Position: The position at which the strongest wind is crossing; by default, this is set to "Muzzle", but can also be set to "Midrange" or "Downrange". Ballistic will adjust your windage (and elevation, if an upwind is specified) based on where the wind is strongest.
• Maximum Range: The maximum range to be calculated and displayed in both the trajectory calculations and charts.
• Range Increment: The increment (step) to be used in displaying the calculated trajectory
• Vital Zone Radius: The size of the vital "kill zone" of the target, used to calculate point blank range. For example, if your vital zone radius is 5 inches, your point blank range will span from your zero to the lowest and highest ranges at which you can hit the target inside that radius.
• Elevation / Windage Units: The units in which to display elevation and windage. This can be MOA, MIL, or click values.
• Y-Intercept: The desired drop (or rise) to compute at zero range. This is normally zero.
• Windage is Zeroed: When calculating spin drift, enabling this option will tell the application that you've zeroed your windage at your zero range. This is particularly useful if calculating spin drift without wind.
• Miller Stability: This is a bullet stability calculation, used to determine if your barrel twist can stabilize a given projectile. Stable values range from 1.3 to 2.0.

Loads and Projectiles