Handloader Calculations

I have a new app out on Android App Market, an internal ballistics calculator and a reloading "Money Saved per Hour" calculator for rifle, pistol and shotgun. There is also a Bullet Stability calculator using the Miller equations, and a Standard Deviation Chart plotter.
In theory it is platform independent (it is essentially an iPhone app) so it should work on the Blackberry, Symbian-Nokia, and Windows phones too.
The internal ballistics calculator is just the old Powley slide rule, you can't use it to roll your own super hot wildcat cartridges, but you see what seating a bullet deeper is likely to do, that kind of thing.
The reloading savings part is a "What's your time worth" calculator, if you reload a lot you may find that spending twice as much on equipment will save you money if it makes you 20% more productive.
There is a Miller Stability calculator for rifle twist.
You can type in a list of numbers, and calculate standard deviation, to compare the consistency of things, from muzzle velocities to component variability, to group size.
Generally, the Blackberry and Nokia programs are looking primitive to the Angry Birds generation, so I am doing things the easy way with a simpler app development system.

Cosine rules for uphill and downhill shooting aren't accurate.

The cosine rule says that at 600 yards at 60° is 300 yards at 0°. Which it is, if you are measuring straight lines. But we aren't.
Type it into a ballistic calculator and see how far off you are. Eyes left, -23" 60° at 600 yards, -16" 0° at 600 yards. Off by 7".
Because:
Gravity is no longer operating at 90° to the bullet, so gravity does less (a fishing rod at 60° sags less than a horizontal one, OK?).
Your sights are higher than the bore, the angle changes the zeroing geometry.
The bullet takes longer to get there, and slows down.


So, you have to use a computer.