As fara s I'm aware you can't take the weapon away from the character entity unless he's dead.
You can, however, have the player receive a weapon through scripts without the player needing to go pick it up.
Place the desired weapon somewhere in the level and give it a script that, upon activation, is given to the player (regardless of distance from the player). Then all you'll need to do is have your character entity's script activate the weapon entity to have it given tot he player.
The one and only,
Only those who sow the seeds of their desires will reap their benefits later.
However, I have seeds of my own to tend to. I don't have time to be someone else's watering can.