online external ballistics software x-ballistics
x-ballistics is a free online external ballistics programm.
no installation required, it runs in a browser, just click this 
link.
- no need to know the muzzle velocity, simply can calculate from 2 points of impact
- trajectory
- sight settings
- 3-DOF for bullets
- 6-DOF for arrows
- metric and imperial units
- multilanguage: english and german
- editor for reticle
Use at your own risk!
To store data, a registration is required.
Registered user can save your data.
The sourcecode of x-ballistics is under GPLv3.
Ballistic Software Arrowmatcher
Arrowmatcher is a ballistic application, released under the GPL. It is for Windows, Mac OS and Linux:
This is a simple tool for mainly crossbowarchers. But it can also used for rifles or other bullets. It can calculate the trajectory of arrows and a little bit more.
Everybody are welcome to post comments at the bottom of each page. Simply click the "new comment" link and a window with the uploadform appear.