Nimoh® Ballistics

Download our FREE cutting edge ballistics software Scientific Shooting Systems


The answers to the questions we get the most are right here.  Click on a question to reveal the answer.  If your own question isn't answered here then please don't hesitate to contact us.

Q1: For how long will your flagship software (Nimoh® Ballistics for Windows) remain free?


Q2: Is there a version for other personal computer operating systems? (Mac, Linux etc.)?

We only provide Microsoft Windows version of the PC software and there are no current or future plans for Mac or Linux.

Q3  Are you going to provide a version of the software for PDA/Smartphone/Handheld/Tablet etc, suitable for use in the field?

Yes, we have current plans in-place for a Handheld version of the Nimoh® Ballistics software which we will be announcing in the near future.

Q4: How do I use the software/What's the best way to start?

Easy. Just start off with the Quick Start Guide. Having said that, much of the functionality is very intuitive and very easy to use.

Q5: Why are there three different trajectory prediction methods (Point Mass, Siacci, Pejsa) in Nimoh® Ballistics?

We think that there is a lot of confusion and misinformation surrounding prediction methods, with many claims, counter claims, and inaccuracies about the applicability and/or appropriateness of a given method . Hence Nimoh® Ballistics takes full advantage of the recognised science to present the smarter rifleman with all the available options.

Q6: How do I find the Ballistic Coefficient (BC) of my bullet?

The best way is to consult the website of your bullet manufacturer. Failing that, ask in the forums. Someone may be able to help but ensure you get a valid backed-up answer (by reference to the manufacturer's site for example).  Failing that, you can use the BC Estimation feature of the free Nimoh® Ballistics for Windows software package.

Q7: Which Drag Model do I use for bullets, G1 or G7?

There are two answers to this question really. The first is (assuming you have the G1 and G7 Ballistic Coefficients - which you must have to have this dilemma), then always favour G7. Other than that, the other answer is to use the Drag Model your BC references (assuming you have only a G1 or a G7 BC). Never use a different Drag Model from the one your BC references.

Q8: Which Drag Model do I use for Air Rifle pellets?

Air Rifle pellets is an interesting one. All BC's for Air Rifle pellets we are aware of reference the G1 BC. Not only do pellet shapes not follow the form of the reference G1 or G7 bullets, but practically all air rifles are sub-sonic giving them an even drag profile anyway. To this end you are better just sticking to the G1 BC as published, or a custom reference if you have one (see the application help for more information on how to use custom references).

Q9: So which of the three trajectory prediction methods (Point Mass, Siacci, Pejsa) in Nimoh® Ballistics would you recommend that I prefer above the others?

Point Mass. Preferably with Doppler-Radar measured Drag Model data such as is as produced by Lapua Bullets for exaample. Failing that, favour G7 and failing that, G1. There is an argument for Pejsa over G1 if you have the patience to analyse your rifle/bullet trajectory profile. Siacci is included purely for reference and should not really be used. (Modified Point Mass by the way is the NATO Standard).

Q10: What are Coriolis and Eötvös?/Are Coriolis and Eötvös Effects really that relevant/significant?

Coriolis is the effect on projectile motion caused by rotation of the earth. The Eötvös effect is actually a component part of Coriolis where there is a (small) sideways deviation to the trajectory, which is referred to as "Coriolis" and an (equally small) up or down deviation to the trajectory known as Eötvös effect. These typically make the most difference at extreme ranges for the projectile in question. Irrelevant mostly at typical "effective" ranges and indispensible at the extreme ranges of long-range shooting.