Weapons of War: World War One and the Evolution of the Assault Rifle

U.S. M-16, Introduced 1964

By Michael Shurkin

The assault rifle is a class of weapon that emerged in the middle of the last century to meet the needs of combat soldiers on the modern battlefield, where the level of violence had reached such heights that an entirely new way of fighting had emerged, one for which the existing weapons were a poor match. The name “assault rifle” is believed to have been coined by Adolf Hitler. Toward the end of World War II, the story goes, Hitler hailed his army's new wonder weapon by insisting that it be called not by the technical name given it by its developers, the Machinenpistole (the German name for a sub-machine gun), but rather something that made for better propaganda copy. A Sturmgewehr he called the new gun: a “storm” or “assault” weapon.

At the beginning of the 19th century, soldiers in Europe fought battles exposed in full view of the enemy. Often they moved, stood, or charged in lines or in close formations, in coordination with cavalry and artillery, mostly in the open. They could do this and have a reasonable chance of surviving in part because guns were relatively inaccurate, had short ranges, and could only be fired slowly.

In response, weapons developers in Europe and America focused on making guns more accurate up to greater distances. First they found ways to make rifled weapons easier to load from the front. Next they found efficient ways to load guns from the rear—the breach—rather than ramming bullets down the muzzle of the gun. Breach-loading guns can be loaded faster, and the technology made it possible to develop a magazine that held multiple bullets at the ready. These types of battle rifles culminated with the guns carried by the vast majority of foot soldiers in the First and Second World Wars, weapons like the American Springfield 1903 and M-1 Garand, or the German Karabiner 98K: long and heavy guns that fired large bullets from large cartridges and had barrels that were 24 inches long. The long barrels and big ammunition meant that these types of guns could shoot accurately at tremendous distances. Both also packed considerable punch: their bullets left the barrel at roughly 2,800 feet per second.

Kalashnikov AK-47, Introduced 1974

By the late 19th century, these new guns, combined with machine guns, which were introduced in the 1880s, and significantly better artillery generated a storm of steel so lethal that soldiers had to protect themselves behind cover or in trenches. As a result, soldiers all but disappeared from sight on the battlefield. Tactics changed to hugging the terrain and firing a lot of bullets at an area in the attempt to stop the enemy from firing back, so that other soldiers could move to a better position. Or, there were quick and bloody skirmishes at close range. There was little for soldiers to see, and often they could not expose themselves to take an aimed shot.

Soldiers wanted a weapon that could fire on automatic other than machine guns, which still fired big-rifle ammunition and demanded something big and heavy to absorb the recoil. 

In this context, big rifles were overpowered and cumbersome. They also didn't fire fast or long enough. One solution that became popular during the First World War was the sub-machine gun, which is a machine gun that fires pistol ammunition rather than rifle ammunition. This smaller, weaker ammo made it possible to have a smaller, lighter gun, but the tradeoff was that they had poor range and offered little “penetrating power.” Many armies treated big rifles and sub-machine guns as complementary weapons, and squads carried both into battle. [The author doesn't address the July 1918 distribution of the Browning Automatic Rifle to the troops of the AEF.  Possibly it doesn't meet his idea of an "assault rifle."]

A better solution was an “intermediate” round that was neither too big nor too little. Generally speaking, the less powerful the ammunition, the lighter and smaller the gun, and the easier to fire it accurately even when firing automatically. Smaller ammunition means one could pack more into a magazine and carry more into combat too. The ammunition could not, however, be as weak as pistol ammunition. It had to be big enough and powerful enough to be sufficiently accurate and lethal at useful distances.

StG 44,  Adopted by the Wehrmacht, 1944

The ammunition the Germans developed for what would become the first mass-produced assault rifle, the Sturmgewehr (StG) 44, was the same caliber as the standard German rifle ammunition (7.98 mm) but with a case that was considerably shorter: 33 mm versus 57 mm. This meant that while the bullet was the same size, it was propelled by a smaller amount of gunpowder. The gun kicked less and was easier to control, even when set to automatic, and fired at a rate of 600 bullets per minute. The 98K it was intended to replace was not even semi-automatic. The StG 44 was not lighter than the 98k, but it had a barrel that, at 16.5 inches, was about half a foot shorter. It also had a 30-round magazine, compared to the 98K's five-round magazine. Of course, the StG 44 packed less punch than the 98K and was not as accurate at extreme distances, but the Germans understood that the StG 44 was deadly enough. Fortunately for the Allies, the Germans did not issue many StG 44s until late in 1944, at which point having a better gun wasn't enough to turn the tide of the war.

Source: RAND Commentary, 30 June 2016