Personally, I don't think the M1 was so innovative so much as it was simple and worked well, something that could not be said for most of the other semi-automatic rifles of the period. The M14 was easily just as good as any other 7.62 NATIO rifle during its day.
The TV series "Combat" had fifteen different directors over the course of its run. Most were of about the right age to have served in WWII and some did. One was a B24 bomber pilot, one a US Marine, one was a decorated cavalry officer and one other served in the army. One at least served in the navy just after the war. Two were foreign born but did not serve in any service.
You are correct, Don H, that the standards of the day did not allow gory scenes and it was television anyway. That also applied to The Longest Day, a very accurate movie about D-Day, June 6, 1944. That movie has the distinction of being one of the few movies that included as actors individuals who took part in the actual events that were reproduced in the movie. Saving Private Ryan more than made up for the lack of gore but some aspects of the movie were a little odd. However, the closing scene at the military cemetary in France (I assume) is like nothing in any other movie, though I have no idea whether or not it was true.
Another highly accurate movie was Tora Tora Tora, based on the book "At Dawn We Slept." Not a lot of small arms employed but the famous incident of the black cook manning a machine gun was there. Supposedly he had never fired a machine gun before. He was decorated but didn't make it through the war.
One very curious war movie was "The Battle of Midway (1942)," which was being produced as the battle was taking place. In fact, John Ford was actually on Midway Island during the battle.
Movies are better than ever.