I'm not going to debate you on the points of science because it is your scientific interpretation of the observable consequences of these theories to make magic work except for the guns. Military/Law enforcement and civilian M4/Ar-15 (the most common rifle in America) have a selector switch; single shot or three-round burst. While you personally feel it is awkward as a restriction, the military and law enforcement as well as the gun manufacturers do not find it in any way limiting. 

The best option is never fight anyone with a gun. Simple as that. If you personally feel it is unfair and somehow more unbalanced than a character that can manipulate unseen energies to make magic work, or have characters that can move at incredible speeds or any of the other events that characters seemingly can do in these role-plays, that's fine. That is your option.