Anyone who can load an M14 (the standard model) without pretty much dismounting the rifle has my compliments. It's a clumsy maneauver supporting the rifle and rocking magazines in and out.QUOTE]
It is not necessary to 'rock' the magazine to get it out of the M14 rifle. Drop the rifle from your shoulder and press the carth with your thumb and push forward. To insert a fresh magazine insert the forward edge of the magazine and pull back and up vigorously.
If you can't remove a magazine without rocking it back and forth, then the magazine or magazine well needs to be adjusted. A well trained person with a properly adjusted rifle should be able to re-charge the M14, including releasing the bolt and reshouldering the rifle in about 5 seconds.....maybe less with lots of motivation.
Don't remember seeing anyone reload an M14 without taking the rifle out of their shoulder, but I suppose if a person's arms were long enough it could be possible.