A thought-provoking question, to be sure. The answer depends much on what we're placing under these two terms.
Through my own understanding of Shamanic practices, Shamanisms, and astral projection, I would say that this is true, at least to some extent. Journeying is a major component of Shamanisms, and to at least some extent "astral projection" is a synonym for some form of journeywork. Whether or not it refers to precisely the same form or method is debatable, and I'm cautious about making too strong of an equivocation. Shamanisms are grounded in an inescapably animistic worldview, and the Western occultism out of which the term and practice of astral projection developed is not. The manner in which the otherworlds are described and the methods by which they accessed are different in some significant ways. I'd consider them both forms of journeying, but beyond that, the similarities may be relatively superficial. I'm not really sure.