Applied Ballistics Glossary
Ballistic Profiles
The following terms explain the key parameters and functions for creating, calibrating and using individual ballistic profiles in the Leica Ballistics App.
Bullet Data
Bullet Diameter
The diameter of the bullet.
Bullet Weight
The weight of the bullet, in grains.
Bullet Length
The length of the bullet from the bullet base to the bullet tip.
Ballistic Coefficient
The ballistic coefficient provided by the projectile manufacturer. NOTE: If one of the Applied Ballistics Custom Drag Models is used, the ballistic coefficient displays a value of 1.000 (CC).
Drag Model
The Applied Ballistics Custom Drag Model (CC) or the standard G1 or G7 projectiles. NOTE: Most long-range rifle bullets are closer to the G7 standard.
Rifle Data
Correction Values
The output format for ballistic elevation and windage corrections. Available options are MIL, MOA, ¼ MOA per click, 1 cm/100 m per click, 0.5 cm/100 m per click, as well as inches and centimeters.
Muzzle Velocity
The velocity at which the bullet exits the muzzle. NOTE: This field is required for the firing solution to perform precise calculations. If you calibrate muzzle velocity, this field can be updated automatically to calculate a more precise firing solution.
Twist Rate
The distance the rifling in the barrel requires to make one full rotation. The twist rate is often provided by the rifle or barrel manufacturer.
Zero Range
The distance at which the rifle is zeroed.
Elevation Offset
An additional modification to the elevation adjustment at zero. This setting is often used with a suppressor or subsonic ammunition. For example, if a suppressor is used and the bullet impacts the target 1 inch higher, the elevation offset is 1 inch. This setting must be reset to zero when the suppressor is removed.
Windage Sight Offset
An additional modification to the windage adjustment at zero. This setting is often used with a suppressor or subsonic ammunition. For example, if a suppressor is used and the bullet impacts the target 1 inch farther left, the windage sight offset is -1 inch. This setting must be reset to zero when the suppressor is removed.
Sight Height
The distance between the axis of the rifle barrel and the axis of the riflescope. TIP: This value can be determined easily by measuring from the top of the bolt to the center of the windage turret and adding half the bolt diameter.
Zeroing Conditions
Zero Temperature
The ambient temperature during zeroing.
Zero Pressure
The air pressure at the location during zeroing (station pressure).
Sight Scale Factor
Vertical
A linear multiplier for vertical scaling. Tracking is not perfect on all riflescopes, so the ballistic solution may require a scale correction depending on the scope. If the turret is adjusted by 10 mrad but the impact is at 9 mrad, the sight scale factor is 0.9.
Horizontal
A linear multiplier for horizontal scaling. Tracking is not perfect on all riflescopes, so the ballistic solution may require a scale correction depending on the scope. If the turret is adjusted by 10 mrad but the impact is at 9 mrad, the sight scale factor is 0.9.
Determine MV / Ballistic Calibration
Range 1 – Range
The distance from the muzzle to the first target.
Range 1 – Bullet Drop
The actual elevation correction required to hit the target at this distance.
Range 2 – Range
The distance from the muzzle to the second target.
Range 2 – Bullet Drop
The actual elevation correction required to hit the target at this distance.
Apply V0
The calculated V0 is transferred to the profile editor.
Apply DSF
The calculated Drop Scale Factor (DSF) is transferred to the profile editor. Calibrating the Drop Scale Factor makes the calculation around the speed of sound more accurate for your specific firearm.
Environmental Data
Wind Speed
The wind speed used in the firing solution. With SPD 10, the wind speed is 10 km/h.
Wind Direction
The direction from which the wind is coming. For example, with DIR 9:00, the wind comes from left to right.
Temperature
The actual ambient temperature.
Air Pressure
The actual ambient/station pressure.
Range Card, Target Card and HUD
Range Card
Displays data for different distances based on parameters entered by the user (temperature, air pressure, wind speed, wind direction). The base and maximum distance can be set individually and the distance increments can be edited.
Target Card
Displays the distance, elevation and windage settings for the different targets (depending on the Ultralight™, Elite® or Professional® software level) based on parameters entered by the user (temperature, air pressure, wind speed, wind direction).
HUD – Head-up Display
The central display and user interface of the Leica Ballistics App, providing access to the profile, measurement data and environmental parameters.
Ballistic Corrections
Aerodynamic Jump Correction
The sum of the elevation solution required to compensate for aerodynamic jump. Aerodynamic jump is the vertical deflection of the projectile caused by crosswinds. If no crosswind component or wind values are required, this value is zero.
Coriolis Correction
The Coriolis correction is the sum of the windage adjustment required to compensate for the Coriolis effect. It is always calculated by the device, although its effect is small unless shooting over longer distances.
Spin Drift Correction
The sum of the windage adjustment required to compensate for spin drift (gyroscopic drift). Example: In the Northern Hemisphere, a projectile fired from a right-hand-twist rifled barrel is always deflected slightly to the right along its trajectory.