Okay, On the top of the .cs you will find "Edit"(i think. Its the second thing that is there)
Click it and search for "Replace"
Then click the upper list(The thing were you can write) and then type inn the weapon's name
In the one that is under you shall type in what you want it to be named accept what it was before
Then click "Replace All"
And there you go, hope you understand, cause i don't understand what i just wrote O_o