The discharge of a firearm with the intent to kill someone is first degree homicide (or occasionally self defense).
It prevents the firearm from discharging before the shooter means to have it discharge.
A long period of jail depending on what the criminal has done.
In general no, but there are certain situations where murder (with or without a firearm) becomes a federal crime.
To prevent a premature or unintended discharge of the firearm. It does NOT replace common sense.
It varies from locality to locality. Check with your local laws. http://forum.pafoa.org/question-answer-40/12359-what-law-discharge-firearm-not.html
Possible but not likely with an ordinary firearm
No one answer- depends on the law where YOU are.
The doctor will discharge the patient from the hospital once they have fully recovered.
Can be if intent was to kill
Not necessarily.
You cannot own a firearm with a dishonorable discharge, which is the most severe discharge there is. However, a "less than honorable" is not the same as a "dishonorable" discharge. If the discharge resulted from a court martial, and the service member was convicted of a crime that would be a felony (punishable by a year or more in prison) then you should consult an attorney for legal advice.
No. However, local ordinances may prevent you from being able to discharge a firearm within town limits and such.