Depending on the conditions, it ranges from 1-10 to one in a few million.
I dont think so... Violence usually leads to more violence. As Gandhi said " an eye for an eye would leave the whole world blind".
The historical cartridge used in the .30-30 lever action rifles/carbines had/has a rounded nose to prevent ignition of the primer in the cartridge directly ahead in a tubular magazine. Recently...
None. A bullet is a bullet, regardless of what material it's made from.
On the sight of the wound, there may be a scar...