# Ballistics math and physics.



## Robert A. Langager (Feb 22, 2002)

What exactly is MOA? I know it is minute of angle. So that would be 1/60th of a degree, based on 360 degree circle, right? Is that a known distance at a certain yardage? I imagine it is figured using good old Pythagorean theorem, or the law of sines? Where can I go to get good info on ballistics calculations? Is there good software for that too?

Robert


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## DuaneinND (Jan 22, 2005)

Generally for the ease of figuring 1 moa is considered 1" at 100 yards, the actual figure is 1.something, I don't have the actual figure in front of me. Using the 1" premis means a 4" group at 400 yards is 1moa.
One very good/interesting book to read is "Custom Cartridges" by Ken Howell- Sinclair International has copies for sale. Tne Sierra Infinity program is an excellent program for downrange ballistics. Quickload will calculate pressures of given loads, fired in barrels of certain dimensions, most of the data is pretty close,but it depends on the accuracy of the information feed to it. The only thing I don't like about Quickload is when I updated from 98 to xp professional, my $150 program won't work and they charge for the update. Sierra on the other hand gave me a new Infinity that was compatable. Other books you will find interesting is "Hatchers Notebook" and PO Ackleys "Handbook for Shooters and Reloades" vols 1&2.

www.duanesguns.com


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## Sasha and Abby (May 11, 2004)

http://www.eskimo.com/~jbm/ballistics/t ... j_dat.html

Try this. You just plug in the varibles... :beer:


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## huntin1 (Nov 14, 2003)

1 MOA at 100 yards is 1.0472 inches, or as DuaneinND says 1" at 100 yards. Makes things easier to calculate.

I like the Sierra Infinity program, the link that Sasha and Abby provided is also a good one, I use that too.

huntin1


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## farmerj (Jun 19, 2004)

check this out too.

http://www.shooterready.com/lrsdemohi.html


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