Here's a link to a previous post about "The Thing". (Down the page a bit)
I originally found Peter Cronhelm's website and downloaded an Excel spreadsheet for ballistics. Peter and I got hooked up we modified it into something it was not. (Peter and I e-mail "The Thing" back and forth many times during the development stage (a never ending process). I don't think Peter had any idea of what he was letting himself in for when he agreed to test the critter each time I changed it.) [img]images/icons/grin.gif[/img]
It's hard to visualize the layout from the little Cassiopea screen you saw at the show but once you've seen it on a proper computer you can easily understand where things are located.
I does a lot of "magic" stuff.
There's the basic data entry section:
wind speed and direction
range increments for the ballistics page
(One thing we discovered at the show was that if you set the MOA value to the "click" value .262 for .25 MOA clicks the readout can be used directly as "clicks" rather than MOA. I think in MOA, some shooters think in "Clicks")
Range based on GPS fixes
Range based on MIL value and target size
Windage and Elevation based on range, wind and slope, either hand entered distance or GPS. (Yes, the wind is calculated for the full wind distance while the elevation is based on "horizontal" distance.)
Elevation and windage correction based on "miss" value(s).
Lot's of little things.
On the main Ballistic data page there is also a section for entering known distance values and an immediate return of the MOA elevation adjustment from the zero setting, wind adjustment and mover hold-off in MILs.
This particular section also has a "Miss" section that allows the spotter to get a MOA correction by entering the vertical and/or horizontal distance in inches for the "miss"
The program will calculate the extra adjustment needed for a second round hit.
The other distance determination on the main Ballistic data page is to calculate distance based on MIL reading, supply the MIL value and the target size in inches and the program computes the distance and MOA adjustments for elevation and windage.
There a page for the standard Ballistics Table, good for creating a "click chart" when used on a standard computer. The increments for the page are controlled from the main Ballistic data page.
There's a Target Reference Point(s) (TRP) page the allows a shooter to input multiple target sites and one Firing Position. The computer will provide scope adjustments in elevation and windage for all the target sites. On the GPS determined position page, one TRP is designated the primary site and the computer "knowns" the wind values for all the other sites. I haven't worked a geographic elevation value nto this page yet and when I do the computer will calculate slope for all the sites also.
The Ranging Ballistic Computer spreadsheet is free. It requires Microsoft's Excel to run on a home PC. The Cassiopea and other handheld computers that have "Pocket Excel" will run the software also.
I'm going to develop a Visual Basic version that's stand-alone when I get a little more time.
ONE SIGNIFICANT DRAWBACK for the little handheld computers is that in bright sunlight the screen is nearly impossible to read unless you get the "backlit" version.
We can't guarantee first round hits.
We can't guarantee your batteries won't fail.
We can't guarantee your wife will be happy with you spending more money on another shooting thing. [img]images/icons/grin.gif[/img]
We can't guarantee the shed you'll be sleeping in will be big enough for comfort. [img]images/icons/grin.gif[/img]
This program is NOT as sophisticated as some others on the market or others that may be in development.
[ 02-08-2002: Message edited by: Dave King ]