You may find this interesting viewing: https://www.youtube.com/watch?v=BNVegwmZiQM
Also, I noticed that when the dork was firing from a prone position with the tripod, he did not make use of the metal shoulder rest that deploys from the butt to rest atop the shoulder. That, and I was trained to fire with my non-firing hand resting over the stock of the weapon to add additional stability. It works well when it's used well.
By the time I got in in the early 1980s, all the problems had been worked around. We had top-notch armorers, and it was drilled into my head to take very good care of that weapon. Warts and all, for me it was a very reliable and accurate weapon.