Spitzer (bullet)

The spitzer bullet (or spire point) is a pointed projectile that is primarily used in small-arms. The pointed nose shape, which was developed for military purposes in the late 19th and early 20th century, was a major design improvement compared to earlier rounder or flatter-tipped bullets because pointed nose shapes were less susceptible to external ballistic factors like drag. By adding a point, projectiles made for fully-powered and intermediate rifle cartridges obtain a lower drag coefficient, which makes them decelerate less rapidly. Lowering the drag coefficient leads to improved external ballistic behaviour. The development of spitzer bullets and long-range volley sights for service rifles changed military doctrines. Area targets at ranges up to could be subject to rifle fire. With improvements in machine guns at the turn of the 20th Century, the addition of clinometers meant that fixed machine gun squads could deliver plunging fire or indirect fire at more than . The indirect firing method exploits the maximal effective range, that is defined by the maximum range of a small-arms projectile while still maintaining the minimum kinetic energy required to put unprotected personnel out of action, which is generally believed to be 15 kilogram-meters (147 J / 108 ft⋅lbf). Spitzer bullets greatly increased the lethality of the battlefields of World War I. Before, during and after World War I, militaries adopted even more aerodynamically refined spitzer projectiles by combining a pointed nose with a slightly tapered base at the rear, called a boat tail, which further reduced drag in flight. These projectiles were known as spitzer boat-tail bullets which increased the terminal maximum ranges of fully-powered rifle cartridges to between . The name "spitzer" is an anglicized form of the German word Spitzgeschoss, literally meaning "pointed projectile". By the middle to the end of the 19th century, European military research had started to examine how to maximise available small arms muzzle velocity through improved projectile design.