Ballistic knowledge–knowing how far your bullet, fired from your rifle in the local atmospheric conditions, will drop at different ranges–can spell the difference between a hit and a miss. If you hunt, you need to know the exact trajectory of your projectiles at given ranges so you can make a humane kill. If you shoot targets for fun or competition, you’ll also want to know exactly what your bullet will do beyond a couple of hundred yards, so you can make first-shot hits. Most importantly, in any shooting situation, you have to know exactly where your bullet will travel. A shot that inadvertently impacts the ground can skip and travel to unintended places.
There are two basic approaches to accurately predicting the vertical and horizontal path of your bullet once it leaves the muzzle. First, you can use a ballistic calculator app on a smartphone. Second, you can use a portable weather meter with ballistic calculation capability.
Ballistic Calculator Applications
Good ballistic apps are plentiful. The one I use, Ballistic AE, is available for iPhones, iPads, and iPod touch devices. (It’s not currently available for Android devices, but there are other apps that provide similar functionality, such as Applied Ballistics, that uses the same ballistics model available in the Kestrel weather meter that we’ll discuss in a minute.)
To oversimplify a bit, ballistic calculator applications calculate the drag models of various projectiles moving at different velocities. If you know the specific projectile you want to fire, and how fast your particular firearm launches it, you can predict with great accuracy the flight path of that bullet.