Applied Ballistics Glossary

Rangefinding made precise and easy.
hunting_leica-ballistics-app

Ballistics Profiles

Bullet Data

Bullet Diameter The bullet diameter. 
Bullet Weight The bullet weight in grains. 
Bullet Length The length of the bullet measured from the heel to tip of bullet. 
Ballistic Coefficient The ballistic coefficient of bullet. NOTE: If using an Applied Ballistics Custom Drag Model (CDM) rather than G1/G7 model, the ballistic coefficient will display a value of "1.000".
Drag Model The model used to create a ballistic solution: Applied Ballistics Custom Drag Model (CDM), G1 Model or G7 Model. NOTE: The AB CDM is a directly measured drag profile for that bullet using Doppler Radar. The G1 model is generally suited for flat based projectiles and G7 is suited for boat-tail bullet designs.   

Firearm Data

Correction Value The type of correction values to use for your solutions. Options include: MIL, MOA, 1/4MOA click, 0.1 MIL click, 0.05 MIL click, Inches, CM
Muzzle Velocity The speed of the bullet as it leaves the muzzle. NOTE: This field is required for accurate firing solutions. NOTE: If the "Muzzle Velocity Calibration" tool is used, this field may be updated automatically.   
Twist Rate The distance it takes for the rifling of the barrel to make one full rotation. Rifle twist is often provided by the gun or barrel manufacturer.
Zero Range The range at which the rifle was zeroed.
Zero Height The vertical relationship between the rifle's point-of-imact versus the point-of-aim. For example, if you zero your rifle 1 inch high of your aimpoint, entering this value will correct solutions to include your zero actual zero height. NOTE: If you adjust your zero, you will need to remove/adjust this value accordingly. Use (+) values for high of point-of-aim and (-) values for low of point-of-aim. 
Zero Offset The horizontal relationship between the rifle's point-of-imact versus the point-of-aim. For example, if you zero your rifle 1 inch right of your aimpoint, entering this value will correct solutions to include your zero actual zero height. NOTE: If you adjust your zero, you will need to remove/adjust this value accordingly. Use (+) values for right of point-of-aim and (-) values for left of point-of-aim.   
Sight Height The distance from the center axis of the rifle barrel to the center axis of the scope. TIP: This value can be easily determined by measuring from the top bolt body to the center of the scope main tube, and adding half of the diameter of the bolt.

Sight-in-conditions

Zero Temperature The ambient temperature during zeroing process.
Zero Pressure The ambient (station) pressure during zeroing process.

Sight Scale Factor

Vertical A linear multiplier that accounts for vertical scaling. Not all rifle scopes track perfectly, so the ballistics solution requires a correction to scale according to a particular rifle scope.  For example, if the measured drop of the bullet is 9.0 mils but the turret is moved to 10 mils, the sight scale factor is (10.0/9.0) = 1.111.
Horizontal A linear multiplier that accounts for horizontal scaling. Not all rifle scopes track perfectly, so the ballistics solution requires a correction to scale according to a particular rifle scope.  For example, if the measured lateral impact of the bullet is 9.0 mils but the turret is moved to 10 mils, the sight scale factor is (10.0/9.0) = 1.111. 

Muzzle Velocity Calibration and Ballistic Calibration

Range 1
Range The distance from the muzzle to the Range 1 target.  Ideally, this should be the range where the bullet is travelling at Mach 1.2.
Drop The actual elevation needed to impact the Range 1 Target distance.
Range 2
Range The distance from the muzzle to the Range 2 Target.  Ideally, this should be the rnge where the bullet is traveling at Mach .8.
Drop The actual elevation needed to impact the Range 2 Target distance.
Set MV Calibrated muzzle velocity will be copied into the profile edtitor.
Set DSF Apply the the calculated Drop Scale Factor (DSF) to your profile. Drop Scale Factor (DSF) Calbration improves the accuracy of solutions in the transonic/subsonic range for your specific firearm. 

Range Card, Targets, HUD

Wind Speed The wind speed used in the shooting solution in the prefered units. For example, a SPD value of 10 is  equivalent to "10km/h". If units are set to MPH units, "10" would equal "10 MPH".
Wind Direction The direction from which the wind is coming using clock-hour format. For example, at a DIR of 9 o'clock the wind blows from your left to your right. Wind blowing from target straight to your position would be a 12 o'clock wind. 
Temperature The ambient air temperature at your location.
Pressure The absolute air pressure (station pressure) at your location.
Range Card View data for various ranges based on user input parameters (Wind Speed, Wind Direction, Temperature, Pressure). The base range, max range, and the range increment can be edited.
Targets View range, elevation, and windage for 5 targets (10 for Elite) based on user input parameters (Wind Speed, Wind Direction, Temperature, Pressure). This is useful for building solutions to known reference points or targets in the field, such as key terrain features, animal travel corridors, or points of interest for animals in the field. 

General

Aerodynamic Jump Correction The amount of the elevation solution attributed to aerodynamic jump. Aerodynamic jump is the vertical deflection of the bullet due to a crosswind. If there is no crosswind component or wind value, this value is zero.
Coriolis Effect Correction The Coriolis effect is the amount of the windage solution attributed to the Coriolis effect. This is always calculated by the device, although the impact may be minimal if you are not shooting at extended range.
Spin Drift Correction  The amount of the windage solution attributed to the spin drift (gyroscopic drift). For example, in the northern hemisphere, a bullet shot out of a right-hand twist barrel will always deflect slightly to the right as it travels.