Adding components to mesh help please =)

so i have a weapon mod that im working on and i have figured out how to add components to a mesh such as a particle system or what ever i can add things to a 3rd person view mesh no problem but the first person view of that mesh (the root) i cannot seem to add things to it where they stay attatched to it…does anyone have any idea what im talking about or any way they can give me some info on this

anyone can help?