I don't think I have ever seen an airsoft gun defined as one of the following.
576-015-0020
Offenses Proscribed by the University
A Student or Student Organization found to have committed any of the following proscribed acts is subject to sanctions under these rules
(8) Possession or use of firearms, explosives, dangerous chemicals, or other dangerous weapons or instrumentalities on institutionally-owned or controlled property, in contravention of law or institutional rules.
If you transport it an a large bag that is not an obvious gun case and don't have it out in public I think you would be fine. If you want to handle your airsoft gun or gear do it in your room with the door closed and only around people you know who are not, with all due respect, uber leftist scaredy cat know nothings. You are in college but not in Eugene so you might find a couple.
Don't let others fear and ignorance stop you from doing things that you are allowed do.