Good question. The statute that prevents cities from messing with CHL holders is 166.173, which reads in part:
161.015 reads in part:Authority of city or county to regulate possession of loaded firearms in public places. (1) A city or county may adopt ordinances to regulate, restrict or prohibit the possession of loaded firearms in public places as defined in ORS 161.015.
So is the stadium a public place? Is it a place of amusement? Is it a park? If we assume for a second that it isn't a public place, then Portland's ban on loaded carry without a CHL wouldn't apply at the stadium since it reads(10) “Public place” means a place to which the general public has access and includes, but is not limited to, hallways, lobbies and other parts of apartment houses and hotels not constituting rooms or apartments designed for actual residence, and highways, streets, schools, places of amusement, parks, playgrounds and premises used in connection with public passenger transportation.
I guess even with all this information I'm still not sure if the stadium would be a public place. My guess is that it is not since admission is required, but I'm not too sure.It is unlawful for any person to knowingly possess or carry a firearm, in or upon a public place, including while in a vehicle in a public place, recklessly having failed to remove all the ammunition from the firearm