When I first started to shoot long distance years ago, I started with the Sierra I-5 ballistic software. I first thought that it would be the answer to my prayers. It had everything I needed and it would account for all the atmospheric conditions that I would encounter while shooting. But when I pulled the trigger guess what, a miss. I thought that because I could not make in field changes, that it was causing the bullet to miss the target. The real problem laid in the way the software accounts for bullet drop. A long time ago a man called Mayevski came up with a standard projectile flight path around the turn of the 20th century that all other bullets would be based off of. The problem is that the standard bullet weighed about one pound, was about one inch in diameter and with a very blunt nose. Which could not be compare to today’s modern bullets. So basing your flight path from this useful but out dated technology became very difficult to do. You had to break down your flight path into different velocity regions and assign a different BC (ballistic coefficiency) in each region. The Lex Talus Corporation has come out with Field Firing Solutions. Software that, instead of using Mayevski drag function, uses a deceleration constant. This allows you to use only one BC value on your flight path. If that wasn’t enough, it gives you the ability to use angle cosine and coriolis drift to calculate your shot. The software was made to give you cold bore shots, and does it very well. Plus, with the ability to put the software on a PDA, it gives you great control over the atmospheric conditions that you will encounter in the field. In my years of shooting, I have seen several types of ballistic software and not one can give me the type of control that this one delivers. It’s very easy to use and understand. In my opinion, to purchase this software would be one of the best choices you could make for shooting long distances.