Campus environments are very leftist because they are run by the hippies of the 1960's and 1970's. That is just the way it is. There are some faculty who are conservative, and more students than you might think who are conservative.
I love to have non-traditionals in my classes because they have a higher maturity level, I do not have to deal with the twenty-something stupidity that a lot of current college students possess (thanks to their stupid, lazy parents and stupid, lazy high school teachers). Non-traditionals also work harder and actually try to think things through. So, stick it out, just be yourself, and get a good education.
As for the hats, etc., my policy is that any time you wear a hat in my class, I deduct 5 points from your total course points. It is in my syllabus, I tell the class that is one of the rules on the first day of class. I do that because wearing a hat in class (and in a lot of other situations) is rude and disrespectful; part of my responsibility is to train my students in what we refer to as professional behaviors.
I wouldn't worry about brass casings, that is perfectly legal. Keep in mind that you cannot have a firearm on campus, so be very careful there; you do not want to be the example for everyone else. I would suggest that you get gun related T-shirts (e.g., NRA, Wisconsin Carry, Glock, S & W) and wear them on campus every chance you get, I do.