Barely a year passes without war playing out somewhere on the planet. Whether it is on the plains and in the mountains of Afghanistan, on the streets of the Somalian capital Mogadishu, or throughout Mexico's many states where a drug war still rages, it seems that humanity thirsts for conflict.
And guns, the ubiquitous tools of war, are becoming ever more accurate. In November 2009, Corporal of Horse Craig Harrison achieved a confirmed kill with his British L115A3 sniper rifle. The distance was 2,475 m (2,707 yd). But no matter how precise firearms become, they still (in general) need a human to point them in the right direction and humans are by their very nature fallible. A 2007 U.S. government report estimated that a staggering 250,000 bullets have been fired by U.S. forces in Iraq for every insurgent killed.
As a vast percentage of those expended rounds will have been used for suppression, lost, spoiled or spent in a myriad of other ways, the figure of a quarter-million is undoubtedly misleading. Still, the fact remains that even a veteran soldier’s aim is often far from perfect.
Luckily for today’s rifleman, many devices have been developed to help him hit his target: night vision and a vast assortment of reflex sights and other optical aids abound, but while these high-tech gadgets are an improvement over the good old iron sight, one of the simplest and most common ways to see where your shots will fall is by using the humble tracer round. Before reliable tracers were invented, a shooter had to watch for the impaction of his bullets in order to discern whether he was firing accurately. However, it is not always possible to see the impacts, especially at long ranges, in low-visibility or when receiving enemy fire. Tracers were first introduced in 1915 during the Great War. Britain’s Royal Laboratory produced a .303 bullet that emitted ‘an erratic white trace for between 50 and 100 yards’. It was not particularly successful and was quickly eclipsed by subsequent designs. Late 1916 saw the introduction of the .303 SPG Mark VIIG. This new round gave off a bright greenish-white trace, was very successful and remained in service until World War Two.
The 3rd of September 1916 brought a great victory for British morale. The war had been raging for two years and German Zeppelins had enjoyed almost complete control of the English skies. Although they caused very little damage to war production, some 528 people had died as a result of the airships’ bombing raids, with a further 1000 wounded (most casualties were civilians), and as such they were a much-feared ‘terror weapon’. So when Lieutenant William Leefe Robinson of 39 (Home Defence) Squadron Royal Flying Corps shot down the first Zeppelin in early September it is no surprise that he earned Britain’s highest military decoration – a Victoria Cross.
Flying his Blériot Experimental 2c, Leefe-Robinson succeeded in igniting the airship’s hydrogen with a Lewis Gun that was loaded with a mixture of explosive and tracer rounds (Pomeroy and new Brock).
A further four of the German bombers were shot down in the months that followed. Out of a total of 115 airships, the German’s then lost 77 of them in rapid succession. By June 1917 they were no longer sent to bomb Britain. Thanks in part to the tracer, the Zeppelins’ almost unopposed reign of terror had come to a sudden halt.
So what is a tracer bullet?
From the outside, a tracer looks identical to any other bullet (usually painted with a red tip). Inside, however, the projectile’s hollow base is filled with ‘a pyrotechnic flare material’ that, once ignited during firing, burns brightly for a period over the course of the bullet’s flight. One patent outlines the pyrotechnical composition as ‘zirconium powder, potassium perchlorate and a suitable binder’, although compositions vary. Tracers are, in essence, simple things, and enabling a shooter to see the trajectory of his bullet brings many advantages. Not only can they be used to good effect when engaging a moving target (making it possible for the user to ‘walk’ the rounds onto the objective), they can also be loaded as the last rounds in a magazine to act as a reminder that the weapon will need reloading soon. The construction of a tracer differs greatly to normal ball ammunition. This means that their ballistic characteristics differ, too, and therefore both projectiles will impact at different places over long ranges.
Today’s tracer comes in three varieties: Bright, Subdued and Dim. Bright are the most common tracers encountered; they burn immediately upon firing and glow through most of the bullet’s flight. Their intrinsic disadvantage is that not only do they give away the user’s position to the enemy but also that, when used at night, they can temporarily disable night vision apparatus with a ‘blooming’ effect. Countering these problems are Subdued tracers which only ignite after travelling one hundred or so yards (and so do not give away the firer’s position as easily) and Dim tracers which, although only glowing faintly, are still discernable when viewed through night vision equipment. In US/NATO usage tracer ammunition is identified by a red tip (Bright), an orange tip (Subdued), or a violet tip (Dim).
The tracer’s incandescent path helps to mark targets for the rest of the squad; indeed sources say that in some cases platoon leaders have entered combat with magazines charged entirely with tracers in order to mark targets for their men. This is perhaps apocryphal though, as a well-trained soldier is taught to be able to clearly indicate an enemy's location verbally. Also, over-use of tracers can leave chemical deposits inside the barrel. To this end, usually they are interspersed among the ball ammunition in a belt or magazine at a rate of 4 ball rounds to every tracer (although this ratio is by no means gospel).
While tracer ammunition is not designed specifically to have an incendiary effect, it is very much capable of igniting the surrounding flora, especially if environmental conditions are conducive. Late July of 2009 saw a significant wildfire rage through 3,000 acres of French scrub land east of Marseilles. Hundreds of firemen battled to bring the inferno under control as it threatened to engulf France’s third-largest city. A thousand homes were evacuated. It was revealed that the fire was started accidentally by a non-commissioned officer allowing the use of tracer rounds (against orders) during a French Foreign Legion exercise at nearby Carpiagne. Ultimately, the combined efforts of the fire departments, their aircraft and a change in the wind direction allowed the conflagration to be brought under control. The soldier was suspended and faced disciplinary action.
War doesn’t stop when the veil of night descends upon the front lines. Indeed, with the invention of night vision systems that allow soldiers to see the battlefield in low-light conditions, the world’s more sophisticated armies have embraced the darkness, and covert missions are regularly conducted under the cover of night. And it is at night that a tracer fire makes for an impressive light show.
Another, more unofficial use for a tracer is as an unconventional cigarette lighter. Readers are advised to use matches!