For one thing, you will not find any at you local gun shops. You will find semi-automatic rifles that look like assault weapons. But that is all. While they look like an assault weapon, they do not function like an assault weapon.
The rifles on the civilian market are only semi-automatics. This means that you can only fire one round per trigger pull. You have only two functions, safe and semi.
A true assault weapon has a third function, burst or auto. Burst you are limited to three rounds per trigger pull. Auto means it will keep firing until you either release the trigger or the magazine is empty which ever comes first.
So much "reporting" today doesn't understand these most important differences. Or they do, but ignore them to slant the story against guns. Either way it destroys the credibility of the story.
I served for 21+ years between active Air Force and Michigan Army Guard. I earned expert qualification with the M-16 rifle in both the Air Force and Guard. After serving in Iraq in the Guard, I became Company Marksmanship NCO for my Company.
The damage done to a person when shot is from a combination of the weapon and the bullet. The weight, velocity, and construction of the bullet are all part of the equation.
The speed of the bullet is the most important factor. If it is going fast enough, it creates hydrostatic shock when it enters the body. This is very damaging to cells. The shock wave can kill cells near the bullet path by rupturing the cell membrane.
The construction of the bullet is important. A solid full metal jacket round does less damage than a softer tip round. The softer the tip, the more energy is lost in the body and the more damage it creates. A solid round can go through more material than a soft point.
The weight of the bullet times the velocity is the bullet's total energy. The heavier and faster the bullet goes, the more material it can penetrate. A heavier bullet can better penetrate cover of person is hiding behind like a wall and still do lethal damage.
The longer the barrel of the weapon, the higher speed of the bullet and the more accurate the weapon is at longer ranges.
You can't judge a weapon just by looks. There is much more to understand. The left's war on weapons is based on keeping people ignorant about what is and isn't an assault weapon. They want you to literally "judge a book by it's cover". They don't want you to know the details.