Only on /. can you get a discussion that includes [[w[:Bluetooth]] technology and ballistics. This is all from a thread about a “Bluetooth Sniper Rifle” that looks way cool.
“Bah, go study up on exterior balistics my friend. Gravity, acting on the bullet is straight down, but if the bullet isn’t traveling perfectly horizontal, then the gravity vector of 32 feet per second per second isn’t being applied at right angles to the path, but at a vector.
So if you are shooting downhill at a 45 degree angle, then that 300 yards you mentioned must be multiplied by the sin of the downward (or upward, they are in fact interchangeable) angle which for 45 degrees is .707 in round terms, making the true horizontal distance traveled only 212 yards, so the fall is proportionatly reduced and the bullet will hit a wee bit higher than the 300 yards over level ground math would indicate. Just a very few inches at 300 yards depending on just how far your piece can reach out and touch someone, but a much larger difference will be seen at the longer ranges and at even higher angles from level.
There are other effects to figure in, such as the distance for the air to slow it down remains at the line of site measured distance of 300 yards so the loss of velocity remains at the 300 yard figure. So does the effect of a crosswind in the drift.” – quote in context