According to Webster's online dictionary, a volume is "a series of printed sheets bound typically in book form;" it is also "a series of issues of a periodical". Issue on the other hand is "the act of publishing or officially giving out or making available" when it behaves like a noun and seems to have no affiliation to it's meaning with magazines and publishing.
However, a look at a page from California State University Libraries, delineates a more precise definition of the word volume. According to this source (http://lib.colostate.edu/howto/gloss.html), a volume is, "physically, a gathering of pages bound together in the form of a book". In this sense, it is identical to the dictionary definition. In addition, though, "Numerically, a volume is a full set of issues (numbers) which comprises a SERIAL volume bound together." And here is where we get to the meat and potatoes of the difference between volume and issue; from this definition, it seems that issues comprise a volume when you are talking about a serial publication (magazine, journal, etc.)
A Spanglish blog dedicated to the works, ruminations, and mongrel pyrotechnics of Yago S. Cura, an Argentine-American poet, translator, publisher & futbol cretin. Yago publishes Hinchas de Poesia, an online literary journal, & is the sole proprietor of Hinchas Press.