There are still people who believe that the AR rifles have fundamental design flaws. They often cite the AK-47 as the model of reliability. This leads to claims that the AK performed better in Vietnam.
There were issues with the fielding of the new M-16. There is much confusion over the problems the M-16 had in Vietnam. Some of this is because of third hand repeated stories of how somebody’s uncle had a bad experience. Here is a great explanation of what really happened.
https://youtu.be/lLYLkrethQA
But what about when you put it in mud? Isn’t the AK better? Glad you asked.
Photo courtesy of the warfarehistorynetwork.com