Towards the end of World War 2, all sides had realized the potential of automatic weapons to a high degree. Automatic weapons outclassed the traditional bolt-action service rifle as they could lay down repeating fire with relative accuracy at ranges often encountered by infantry. Such firearms could also be fed from larger ammunition supplies before requiring a reload. The automatic weapon - finding success in other forms such as the German MP40 and the Soviet PPsH-41 submachine guns - was here to stay and with it, came the rise of the "assault rifle" - a class of weapon that provided the portability of a submachine gun/carbine with the repeating firepower of a machine gun. To the Germans, the assault rifle was known as the "Sturmgewehr" - meaning "Storm Rifle" - the image being that of the German infantryman storming the lines of Allied troops and mowing them down in deadly fashion. The first "true" frontline operational assault rifle became the German StG44 - dubbed the "Father of Assault Rifles" in today's literature. This weapon centered around the 7.92x33mm Kurz ("Short") intermediate cartridge firing from a 30-round, curved detachable box magazine. The weapon featured a fixed stock, gas-operation with a tilting bolt system and went on to be produced in 425,000 examples for the German Army before the end of the war. Like most first-run attempts, however, the StG44 was not a practical weapon to mass-produce for a dwindling wartime economy and its overall weight was subject to some scrutiny.
A resulting project then grew out of the StG44 initiative with the goal to provide the German Army with a more cost-effective, manufacture-friendly solution that also proved lighter in the field. Design work began in 1944 and the new weapon certainly bore a resemblance to the preceding StG44 series to some degree. Testing of a prototype - known as the "Gerat 06" - ensued. The Gerat 06 employed a roller-locked, short recoil mechanism with a gas-operated piston. After a revision which dropped the gas system and introduced the "roller-delayed blowback" breech system, the prototype remerged as the "Gerat 06H". The weapon was then assigned the formal designation of StG45(M) and production was set to begin. However, the end of the war for Germany in May of 1945 signified the end of development to all ongoing German projects - including the promising StG45. Some sources state that as little as 30 units were ever completed - as such, the StG45 never existed beyond a few prototype forms and perhaps some evaluation models. It is known that the system was to enter live troop evaluations before the end of the war. In any case, the StG45 represented the final evolution of the assault rifle for Hitler's Germany.
Externally, the StG45 was of a conventional design with its fixed wooden shoulder stock, angled pistol grip, and a receiver fitting the barrel assembly. The magazine was set in a traditional fashion ahead of the trigger group with all pertinent internal functions housed in the receiver. A charging handle was set to the receiver side with a prominent protrusion. A fire selector was set near the thumb for quick access. and included three modes labeled "S", "E" and "D". A rear sight was fitted ahead of the receiver while a forward site sat atop the muzzle. Construction of the receiver was of steel stampings with welding at certain joints. Magazines were to be curved in the traditional sense and included a 10-round capacity version for testing and a 30-round capacity version intended for the full-scale production model (the StG45 is oft-pictured with the shorter 10-round version). All told, the StG45 effort was roughly half the cost and material required to produce when compared to the earlier StG44 series. It also weighed in at under 9lbs to the StG44's 10lb empty weight.
After the war, it was quite common to find German engineers having relocated their talents to other countries. Some Mauser personnel ended up in France where work continued on a similar automatic weapon firing the US 30 M1 Carbine cartridge with the roller-delayed action but this was ultimately abandoned due to lack of funds. Engineers also made their way to Spain where they worked for the government-sponsored CETME group which refined the roller-delayed blowback action into a workable prototype firing a 7.92mm cartridge. The Spanish government took delivery of a modified form firing a low-powered 7.62mm CETME cartridge as the "CETME Model 58" of 1958 while the weapon was also marketed to the West German Army which accepted the weapon for local production through the Heckler & Koch concern as the "HK G3 Battle Rifle" of 1959 - this firing the full-power 7.62x51mm NATO cartridge. In these ways, the German wartime roller-delayed blowback system of operation endured and went on to be used in a variety of HK products thereafter (including the excellent HK MP5 submachine gun), thus proving the concept a sound alternative to more expensive gas-operated weapons.