I would like to weigh in here, you can choose to accept my advice or not but please no flaming.
I've seen people wearing paintball gear on the bus, pod's (to carry paint in), bdu's, vest, and backpack.
If you look like a paint baller it might attract less attention (oh look it's another paintballer going out to the field) than the other option (OMFG itz n Aussie terrorist 1n c4mo with 4 gun, h3's g01ng to k1ll u5 41l !!!111!1oneone!11!!!).
SO just get a getup that looks like you're a paintballer then put your AS stuff in a bag (drop leg, webbing w/e) and your gun in a rifle case (that gun case is carrying a paintball gun).
ಠ_ಠLess QQ more Pew Pew
READY TO >> RACE