Your browser version is outdated. We recommend that you update your browser to the latest version.


News Flash

Jan 2022: Release of app update.

Feb 2021: Added Utilities to calculate Stability Factor, Spin Drift, Coriolis and Eotvos effects, and speed of sound. 

The 2022 version comes pre-loaded with 5 stored profiles that can be modified and saved by the user.  This will speed up data entry and allow the user to save profiles of favorite bullets and rifles.


The APP has 3 input screens.  The first screen takes information about the bullet such as calibre (diameter), weight, and muzzle velocity.  The second screen takes atmosphere data such as temperature, elevation ( which is converted to pressure), and wind.  The final screen takes information related to the rifle and scope.


Helps are identified with a ? and provide an explanation about  the required input data.

Once the input data has been entered, tap on Results to calculate and display the trajectory data.  While the results below are only shown to 400 yards, the data are written out as long as the bullet's speed remains above the speed of sound.