The REAL Heroes of the M1 Carbine - not "Carbine" Williams
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The Hollywood-spawned mythos of the M1 Carbine is that it was created by David Marshall "Carbine" Williams. The reality is far different. In real life, Williams was talented, but short-tempered, stubborn, and unable to work effectively as part of a team - and a cohesive, cooperative team is what the M1 Carbine required.
While Williams was off sulking about how the work was being done wrong, a team of Winchester machinists and engineers including William Roemer and Fred Humiston were actually making it happen.
The most impressive anecdote of the whole story, to me, is from when the solitary Winchester prototype broke its bolt in the middle of the final testing. Fred Humiston was representing Winchester at the trials, and he was told that if he could provide a new bolt within 24 hours the gun could continue the trials - but he could not take the gun off the testing ground. So Humiston went back to the Winchester shop and made a new bolt from memory (no drawings yet existed for the gun) and without being able to test-fit it in the gun. When he returned the next day, his new bolt dropped in perfectly, and the gun went on to win the trials. That is an epic feat of skill, and it is really a shame that he does not get more recognition for it.