How should I fill in Custom Weapon Model item?

[Max66888]

When I equip this Custom Weapon Model, the first person can't see it
The third person can't see it, only throw it out and preview it
But when I re-enter the game, everything is normal again.

1. Is this because csgo must be reloaded to see some features of external materials?
2. I want to know how to fill in these two columns when my model does not have worldmodel and dropmodel Can i leave it blank?
   

[nuclearsilo583]

drop model is optional. but you should have the world model use valve's default model for that weapon. Extract the default world models from .vpk