astral projection seems to be varied per person, personally I find it is like my body is a coat or an alcove.
If I want to go somewhere specific, for example to my auric bound I think and picture, Laura, then step out onto the relm and I'm near her. It doesn't always work and the defences I put around her even stop me projecting to her some times but that is that.
If something has decided to come and naw on my spiritual ass I just step out of my bdy, I can still feel me breathing, being a body, but I am also in the spirit relm. I've also noticed that if I do fight something in the spirit relm my body goes through the motions which can be quite funny.
Anyway it seems to be varied, personally I'm not sure on the dream thing, I'd describe those as visions rather than projection but each to there own