German ordnance began looking for a military selfloading rifle to augment the K98k as early as the 1930s, although the pressures of war initially made that development a second priority. By 1941, though, two competing designs from the Walther and Mauser companies had been developed to the point of mass production, as the Gewehr 41(W) and Gewehr 41(M) rifles. These both shared a gas-trap operating system to comply with an HWa requirement that no gas ports be drilled into the barrels. When it came to locking systems, the two designs differed greatly, with the Walther being the more successful of the two. Thousands of examples of both designs were put into field testing, mostly in the East, and it because clear that the gas trap system was not suitable for combat. The Walther company responded with a new version of their design which used a much more modern short stroke gas piston, basically copied from the Soviet SVT-40 rifle.

The G43 was very quickly recognized as a significant improvement over the G41(W), and was very quickly put into production, with approximately 400,000 being manufactured by the end of the war. Well, I found an example of the G43 that I could shoot (thank you, Mike) and took it out for some video...