unless it's cheap p.o.s. or a single action revolver. don't want an AD.
You aren't prohibited from openly carrying a weapon in Colorado, but different municipalities have different rules. They won't throw you in jail if you carry in Ft. collins, but you will be talked to. Also, if you have a concealed carry permit, you MUST carry concealed, or not at all. You forego the privilege of open carry when you sign the document for concealed carry.
Also, if you have a CCW the info is linked with the CDOT so cops who pull you over know that you're likely armed. Don't get me started.