Using a figure from a U.S. government publication I would like to use a figure from a U.S. government publication in a research paper that I will submit for publication in a journal.

In particular, I would like to use Figure IV-1 from JP 4-03.

From this post it seems like you have to get permission when reprinting figures, but my reading of Section 3.1.2 on this government website dealing with copyright seems to say that there is no copyright on the publication.

If this is the case, will a caption like the following:

Fig. 1  Notional overland fuel distribution, reprinted from Joint Publication 4-03,
        Joint Bulk Petroleum and Water Doctrine (U.S. Joint Chiefs of Staff, 2016)


where I cite the publication and make it clear it is not my own image be sufficient?
Yes, this is sufficient.

By law, all US federal government publications are in the public domain, and can therefore be reused for any purpose, without permission, without violating anyone's copyright. Of course, you still need to credit the source of the image to avoid plagiarism, but that's exactly what you've proposed.