You wouldn't need the damping factor on the 301 redirect. Unlike pages that can contain many links, a redirect has exactly one link. Taking out the damping factor for redirects only would not prevent the algorithm from stabilizing.
Without the damping factor, it would basically be that a page many urls: its canonical url, and all the urls that redirect to it. Or in other terms, the page and all the urls that link to it are treated as a single document.