If people want a gun to commit a crime, they wont stop committing a crime to get it.
I do not think that the guy who wants to murder someone with a gun will stop doing it just because he commits a crime by getting a gun illegally...
Weapon laws are fine as they are right now. You are allowed to buy a gun. It is rather hard, the guy who wants a gun needs to do all kinds of tests, you need a clean crime record, and it is rather expensive and takes time. Besides that, you are not allowed to buy any sub machine guns, rockets launchers etc. That is fine.
The law just needs a simple addition/change. Wearing guns in a concealed way should be allowed. If you would be allowed to wear it underneath your jacket (concealed) maybe it would help with the crime rate.
As a robber or a rapist, I would think twice if I really want to rob that person. Maybe he/she is wearing a gun.