The difference is when you're at the airport, you're on your way to your new place of sojourn or returning to your residence from your trip. Unless you're at the airport just to eat or hang out, then that's the difference.
According to the NY Supreme Court (in 1890) Wittenbrock v. Mabius, 10 N.Y.S. 733 :
Sojourn refers to a temporary stay by a person who is not just passing through a place but is also a permanent resident.
In other words, the definition of sojourn is a temporary residence, as that of a traveler in a foreign land, a sojourner; to have a temporary abode;
to live as not at home.
If you accept that definition as legal precedence, then the airport and intermediate hotel rooms are not considered places of sojourn. You can't be "passing through", but rather making that your "temporary residence" away from home.
Hawaii allows for intermediate places -- places between changes in your "places to keep". That's why the airport, a hotel room, or a stay at a friend's house en route to your home or place of sojourn are allowed.
"Between" is pretty broad, since it doesn't include verbiage like "directly" or "nonstop". If your friend lives BETWEEN the range and your residence, and you intend to return home after being at the range, then the law permits you to be at your friend's home for an unspecified length of time.
When laws are ambiguous, the ambiguity is to be interpreted in favor of the defendant. Rule of Lenity:
http://www.duhaime.org/LegalDictionary/R/RuleofLenity.aspxThe question becomes, is the wording of the statute able to meet the legal definition of "ambiguous"? If so, "between" has more than one meaning.
Stopping between one legal place to possess a firearm and another is legal -- like an airport -- or a friend's house. You just can't go from home to friend and back home.