maybe if you fire it hard enough
no piranhas can not bite through kevlar body armor at all do not try it
The protective plates, depending on the age of it, will be steel, ceramics, or kevlar.
Body armor is made of Kevlar.
I don't understand what your asking but, kevlar body armor is an example of a layered fiber that catches the bullet while dissapating its energy, if that's what your asking.
Vehicle body panels, hoses, belts, gaskets, tires, clutches, brake pads, & body armor for vehicles can all be made of Kevlar.
The most common brand of body armour by far is Kevlar.
It depends on how thick the Kevlar vest is.
Kevlar level IV
There are many materials with bullet proof properties including Kevlar, Lexan, Titanium, Steel and Carbon Composites. Keep in mind that "bullet-proof" is a relative term. Armor-piercing bullets are designed to be able to penetrate most of these so-called "bullet-proof" materials that will do a decent job of stopping normal (non-armor-piercing) rounds.
First and foremost, it is a movie. Second, Navy SEALs do not always wear kevlar armor. It depends on the mission and the mission objectives. Sometimes the additional weight of a kevlar vest would be prohibitive.
There's no such thing as a good metal for body armor. Kevlar is best.