Small arms science and history are both areas of great interest for me, and the Defense Technical Information Center (DTIC) is the primary source of the historical documents I use to feed this interest. DTIC is a wealth of information on all defense topics, and the information contained there pertaining to small arms seems near-endless. Every week from now on, I will be sharing a document from DTIC that is important to both small arms history and science, here on The Firearm Blog.
To start, I’ll be posting a very technical article, but one that was vital to the development of the modern infantry rifle: The Theory Of The Motion Of A Bullet About Its Center Of Gravity In Dense Media, With Applications To Bullet Design, published by Aberdeen Proving Ground in January of 1930 (three decades before the fruits of its research would reach the hands of US troops). Weaponsman.com, an excellent blog, has covered it previously, which doesn’t at all dull its contents. Beyond its Tolstoy-esque title lies pages of equations describing – among other things – a fundamentally simple principle: When a projectile hits a dense medium, such as water or tissue, it will lose stability and yaw within a proportionally shorter distance than a larger caliber projectile, all other things (such as velocity, projectile shape, and density) being equal. In other words, a .25 caliber projectile identical to a .50 caliber one in every way but size, and moving at the same velocity, will yaw and deposit its energy into a target within half the distance of the larger one.
Upon this principle, the then-nascent concept of small caliber, high velocity ammunition was based, one which has since come to dominate the arena of infantry weapons for half a century and counting.