Those things had a maximum range of 20 miles, but 10 miles was more likely. Was that far enough away to not get severe radiation poisoning, or was manning one of those guns a suicide mission?
From what I've read, if you were 10 miles away from a Hiroshima-level detonation, you wouldn't be in
too much danger from the direct effects of the bomb apart from flash blindness.
For a ground burst generating lots of fallout, being
downwind 10 miles away would be a problem.