What is ballistics? Well, like love it’s, complicated. But if you have around 20 minutes, this video of a vintage U.S. Army training film does a pretty good job of demystifying the multifaceted subject.
The film, circa 1949, touches on all three forms of ballistics – internal, external and terminal. And it gets into some more complex subjects, of which some shooters unfortunately are never exposed.
On this point, the film does a superb job of explaining how the physical shape of a propellant actually influences its burn rate and pressure it produces. Good info, especially for those who wondered how some modern gunpowders can achieve higher velocities, with reduced chamber pressure.
As kind of a fun twist, the film isn’t purely concerned with ballistics in regards to small arms. It also applies the concepts to artillery and missiles. Even so, it’s worth an entire watch, if you’re looking to bone up on the subject.
More than anything, the video will make you appreciate how far we’ve come regarding ballistics in the half-century since the film was made. Just be happy that putting together ballistic data on your firearms doesn’t require a room-sized “computing machine” or a slide ruler, for that matter.
Philip Massaro’s next important reference on reloading — Understanding Ballistics: Complete Guide to Bullet Selection