As much as the artillery is considered the king of the battlefield, it faces a formidable danger from Tanks firing at its positions. Neutralizing these solid armored hunters became nearly impossible, until recent times. But the Anti-Tank rifle is altogether a different animal capable of stopping tanks in their tracks.

The first tanks, beginning with the British Mark I launched against the German trenches in World War I, were nearly impregnable to ordinary rifle fire. Most armoured cars were similarly invulnerable, but troops rarely faced armoured cars, as they could not navigate the landscape of trench warfare very well.

As much as the artillery is considered the king of the battlefield, it faces a formidable danger from Tanks firing at its positions. Neutralizing these solid armored hunters became nearly impossible, until recent times. But the Anti-Tank rifle is altogether a different animal capable of stopping tanks in their tracks.

Though tanks and armoured cars were vulnerable to artillery, mortars, and grenades, infantry was at a significant disadvantage when facing armoured fighting vehicles since they had no effective direct fire weapon, with the exception of the ubiquitous trench mortar, improvised on the spot.

In the direct fire mode, this weapon was manhandled by German infantry over the front of a trench wall and fired at low angles by eye at approaching enemy vehicles. Though somewhat effective, these actions were obviously very hazardous to any desperate mortar crew for a number of reasons.

The first attempt at boosting penetrating power was the so-called ‘reversed bullet’. This used the same cartridge and bullet as the regular round, but the bullet was reversed and an increased propelling charge was used.

The next development was a special armour-piercing bullet, the K bullet (in German Patrone SmK Kurz 7.92 mm), which could also be fired from the regular infantry rifle.

It had an increased propelling charge and a steel core bullet. This had about a 30% chance of penetrating the 8 mm armour of contemporary tanks if it struck the armour at a perpendicular angle.

Both types had their specific advantages and disadvantages: for example, the K bullet was more expensive to produce and therefore was generally only issued to snipers and other advanced marksmen who could use it more effectively; the ordinary infantryman had to make do with reversed bullets, which were far less effective and had to be used in closer proximity to the target (and, therefore, other anti-tank weapons such as grenades, mortars, or artillery were preferred).

In addition, both types of round damaged the rifles due to the higher propellant load and the resulting higher muzzle velocities and pressures: firstly, service life of the rifle barrel was decreased significantly because of the increased wear.

Secondly, the higher pressure created in the chamber could jam the bolt, leading to the extractor claw failing to extract the cartridge and only breaking off the cartridge rim, leaving it stuck in the chamber.

The strain of firing the increased charge could also burst the chamber of weaker and older rifles, at best destroying the rifle and at worst injuring or killing the rifleman.

For these reasons, the K bullet and reversed bullet were not popular with the troops. Nevertheless, it gave the infantry a chance to stop a tank in an emergency, or at least injure or kill some of the crew if a bullet penetrated.

Even as the rounds were introduced, tanks were being designed and built with thicker armour rendering these rounds largely ineffective, though they remained in use against the older designs and armoured cars.

The first purposely-designed infantry anti-tank rifle was designed by Germany. This Mauser 1918 T-Gewehr large-calibre rifle was capable of penetrating the armour of the newer generations of tanks and allowed a chance at stopping them. However, other techniques were still preferred[citation needed].

The high recoil of the rifle was very hard on the firer, sometimes breaking the collar bone or dislocating the shoulder. Although the rifle was unique to its role, it was a development of the Mauser rifles and high-powered British sporting rifles that had preceded it.

The 13.2x92mm (0.538 in) cartridge was not unusual either, some 0.50 in firearms having been fielded in land warfare with the relatively new and more powerful (as compared to black powder) smokeless powders of the era.

During World War I, a half-inch high velocity round was being developed in the US at the same time for use against aircraft. It would be used with the Browning-designed .50 calibre machine gun.

This round was based on current US .30-06 calibre infantry ammunition. When word of the German anti-tank shell spread, there was some debate as to if it should be copied and used as a base for the new machine gun cartridge.

However, after some analysis, the German ammunition was ruled out, as its performance was inferior to the modified Springfield .30-06 round and was semi-rimmed, making it difficult to feed into an automatic weapon. The Browning M2 .50 cal machine gun would, however, go on to function as an anti-armour machine gun.