July 28, 2007

Mil Dot Calculation Software

As many of you know, I have an interest in long range shooting. Here in Texas, there are quite a few shooting ranges that sport distances over 300 yards. A popular feature found in modern rifle scopes is the mil-dot reticle.

A mildot reticle is a tool intended for range estimation. The idea is that you would have a visual of an object for which you know its size (a Texas STOP traffic sign measures 24 inches) and size it against the mildot reticle equipped optic (binoculars, spotting scope, rifle scope, etc.). Then you would use a formula that divides the know object size by the mildot measurement and that would give you the rage or distance to the object. This can be very useful when hiking and/or during land navigation exercises, but indispensable when doing bullet drop compensation adjustments on your rifle scope.

There some software programs out there that perform the computations for you. Yet, I can tell you that it is not so practical to lug around a laptop in the wilderness or an urban battlefield. This is why I always knew that the perfect use for the Nokia 770 is to become a field computer. With its long battery life and aluminum protective cover, the 770 is the ideal companion in a BDU cargo pocket. The Nokia N800 is very capable and very nice in a Starbuck's coffee shop but unfortunately lacks the battery life and the ruggedness of the 770.

Enter Maemo and Mono to the rescue. MilDotCalculator is a Gtk# application that helps you with the unit of measure conversions and the divisions done to achieve the range estimation provided by the mildot reticle. I wrote the software a few weeks before the Mono developers meeting of 2006 but finally have polish it enough to have it run on the 770.

mildotcalc screenshot

I found a very promising shooting simulation software on the Internet that has a demo of its Mil Dot Ranging Classroom on-line. When use with MilDotCalculator you get a better sense of what I been trying to explain.

MilDotCalculator is open source and free of charge to any outdoors enthusiast (hikers, hunters and counter-snipers). You can always find utilities that help in similar tasks for Palm OS an/or Windows Mobile, but this one is powered by Mono.

You can find the MilDotCalculator debian package for Maemo here. A tarball containing the source code for the debian package as well as for the application can be found here.

Posted by martinf at 10:39 AM | Comments (2)