By 1940, it became apparent that some form of a semi-automatic rifle, with a higher rate of fire than existing bolt-action rifle models, was necessary to improve the infantry's combat efficiency. The Wehrmacht issued a specification to various manufacturers, and Mauser and Walther submitted prototypes that were very similar. However, some restrictions were placed upon the design:
no holes for tapping gas for the loading mechanism were to be bored into the barrel;
the rifles were not to have any moving parts on the surface;
and in case the auto-loading mechanism failed, a bolt action was to be included.
Both models therefore used a mechanism known as the "Bang" system (after its Danish designer Søren H. Bang). In this system, propellant gases were captured by a cone-shaped gas trap at the muzzle, which in turn deflected them to operate a small piston which in turn pushed on a long piston rod that opened the breech and re-loaded the gun. This is as opposed to the more common type of gas-actuated system, in which gases are tapped off from the barrel, and push back on a piston to open the breech to the rear. Both also included inbuilt 10-round magazines that were loaded using two of the stripper clips from the Karabiner 98k, utilizing the same German-standard 7.92×57mm Mauser rounds. This in turn made reloading relatively slow.
The Mauser design, the G41(M), failed. Only 6,673 were produced before production was halted, and of these, 1,673 were returned as unusable. Most metal parts on this rifle were machined steel and some rifles, especially later examples, utilized the Bakelite type plastic handguards. The Walther design was more successful because the designers had simply ignored the last two restrictions listed above.
These rifles, along with their G41(M) counterparts, suffered from gas system fouling problems. These problems seemed to stem from the overly complex muzzle trap system becoming excessively corroded from the use of corrosive salts in the ammunition primers, and carbon fouling. The muzzle assembly consisted of many small parts and was difficult to keep clean, disassemble, and maintain in field conditions. The rifle was redesigned in 1943 into the Gewehr 43, utilizing a gas system somewhat similar to that on the SVT-40 and a detachable magazine.
G41(W) rifles were produced at two factories, namely Walther at Zella Mehlis, and Berlin Luebecker. Walther guns bear the AC code, and WaA359 inspection proofs, while BLM guns bear the DUV code with WaA214 inspection proofs. These rifles are also relatively scarce, and quite valuable in collector grade. Varying sources put production figures between 40,000 and 145,000 units. Again, these rifles saw a high attrition rate on the Eastern front.