Bullet Library
Select a bullet from the list or enter in the properties below

Input and Output Units
Input Units Mixed
English
Metric
Output Units MILS
MOA
Inches
Bullet Properties

BC

[?]

Ballistic Coefficient
Ballistic Coefficient (BC) to either the G1 standard or the G7 standard. If both G1 and G7 data are provided, it is best to choose the G7 value for HPBT type bullets.

G1
G7

Weight

[?]Bullet Weight
The weight of the bullet as provided by the manufacturer.

grains

Diameter

[?]Bullet Diameter
The diameter of the bullet as provided by the manufacturer.

inches

Length

[?]Bullet Length
The length of the bullet as provided by the manufacturer. If unknown, mulitiply bullet diameter by 4.2.

inches
Gun Properties

Muzzle Velocity

[?]

Muzzle Velocity
How fast the bullet leaves the rifle as measured by a chronograph. For very accurate results, remember to account for the velocity lost in the 10-15 feet between the muzzle and the chronograph. As a rule of thumb, a bullet looses 5-15 fps in this short distance.

fps

Zero Range

[?]Zero Range
This is the range at which your rifles Point Of Aim (POI) equals the Point Of Impact (POI). A Zero range of 100 yards or meters is encouraged for several reasons, including insensitivity to atmospheric conditions, and accounting for inclined fire effects.

meters  

Sight Height

[?]Sight Height
How high the scope centerline is above the bore centerline. This is typically between 1.5" and 3.5".

inches

Twist Rate

[?]Twist Rate
How many "inches per turn" is your rate of rifling twist. This number is used along with other inputs to determine the stability and related trajectory metrics. Typical value for this input is between 1:7" and 1:13".

inches
Environment

Wind Speed

[?]Wind Speed
The absolute magnitude of the wind speed.

mph

Wind Direction

[?]Wind Direction [Clock Direction]
The direction in which the wind is coming from in terms of clock hands. Example: If the wind is blowing from the left to right and slightly into your face, it would be 10 or 11 o'clock wind.

o'clock

Temperature

[?]Air Temperature
The atmospheric temperature. Because there is a great sensitivity to atmospheric temperature, it is recommended that this data be provided by using a local weather station or handheld weather meter.

F

Pressure

[?]Pressure
Station Pressure

inHg      

Humidity

[?]Humidity
Relative Humidity

% RH      
 
Target

Heading

[?]Direction of Fire
The heading to the target as referenced to true north. The direction shuold be entered in number of degrees from North (0 degrees).

degrees

Inclination

[?]Inclination
This is the uphill or downhill angle to your target and is measured with an inclinometer (angle indicator). The value will be positive for look-up angles, and negative for look-down angles. Small look angles, like less than 5 degrees can typically be ignored with little consequence even for long range shooting. If the angle exceeds 10 degrees it becomes increasingly important to account for.

degrees

Latitude

[?]Latitude
The latitude position of the shooter on the Earth.

degrees

Target Speed

[?]Target Speed
The speed of the target movement.

mph

 



Sight Scale Factors

SSF - Elevation

[?]SSF - Elevation
Input that describes how much your reticle actually moves in response to a given adjustment. For example, if you dial 40 MOA on your scope and it only really shifts the point of aim by 38.5 MOA, you need to apply a sight scale factor (SSF) to account for this, otherwise your scope adjustments will not result in the proper aim.

  

SSF - Windage

[?]SSF - Windage
Input that describes how much your reticle actually moves in response to a given adjustment. For example, if you dial 40 MOA on your scope and it only really shifts the point of aim by 38.5 MOA, you need to apply a sight scale factor (SSF) to account for this, otherwise your scope adjustments will not result in the proper aim.

  
Zero Shift Offsets

Zero Shift - Elevation

[?]Zero Shift - Elevation
If your POA does not exactly equal your POI at the zero range, you can enter how much the group is off center. In other words if you have 1/4 MOA clicks on a scope and the zero is 0.1" high, you can enter this here to account for the error that's less than 1 click. Use negative to indicate down, positive for up.

  

Zero Shift - Windage

[?]Zero Shift - Windage
If your POA does not exactly equal your POI at the zero range, you can enter how much the group is off center. In other words if you have 1/4 MOA clicks on a scope and the zero is 0.1" right, you can enter this here to account for the error that's less than 1 click. Use negative to indicate left, positive for right.

  
Range Card Properties
Start Range
Stop Range
Step Size