Why the Allies never copied Germany's MG 42 machine gun

The MG 42: the machine gun nobody dared to copy in the middle of a war

A paradox: the United States, with the most powerful industry on the planet, tried to copy it in 1943/44 and failed. It copied it later, in Vietnam, as the M60. And when it wanted to improve on it, it went back to the German design from forty years earlier. Why did nobody clone it on the fly? Because copying a weapon isn't copying a blueprint: it's copying machines, processes, tolerances and, above all, an entire military doctrine.

The problem wasn't the steel, it was the doctrine

The German squad revolved around the MG42. Each section carried two or three of them, integrated into the assault. The Allies didn't: the BAR was a First World War automatic rifle, with a magazine of only 20 rounds, no quick-change barrel and a rate of fire that scared nobody. The British relied on the Bren, and for sustained fire they had the Vickers and the Browning .30. Switching to the German model meant retraining the entire infantry —you can't go from playing like Barcelona to playing like Getafe in a day— and replacing a logistics system that, for all its shortcomings, worked. And let's not forget the business side: every country had its factories, its patents and its contracts, and admitting that the enemy's equipment was superior didn't antiestéticature in military marketing manuals.

Copying isn't cloning: the lesson of the T-34 and the B-29

There's an industrial reason few people mention. To copy the T-34, Germany needed to replicate the exact machinery, the processes, down to the metric system it was built with. The Soviets took years to clone the American B-29, and it came out slower and heavier because of differences of fractions of a millimetre in the sheet metal. In the middle of a war, an effort like that means producing no weapons for years. That was impossible to afford.

The secret lineage: from the MG42 to CETME and the M60

The story doesn't end in 1945. The roller mechanism of the MG42 inspired the Spanish CETME and, through it, the G3. The American M60 tried to "improve" the German design, failed and ended up returning to the original scheme, forty years later. Even the Spanish army kept using the MG42 in recent times. Proof that the design was so good that, when people tried to surpass it, war and the market delivered the verdict.

The price of an unmistakable sound

It had one serious flaw: when firing, it made a noise like an old saw. The first burst gave away the position and all the enemy fire converged on it. That's why short bursts were used. Even so, it was so antiestéticared that the Russians captured them and kept them; the Germans did the same with the PPSh. Compatible ammunition, of course, was the problem. But the respect wasn't.

The conclusion? The Allies didn't copy the MG42 because they couldn't copy the doctrine that made it lethal. The rest are textbook excuses.