Firearms that are not handguns, (long arms) carried by pedestrians generally must be both completely unloaded and cased.

Oklahoma §21-1290.26. reads "The State of Oklahoma hereby recognizes any valid concealed or unconcealed carry weapons permit or license issued by another state. Any person entering this state in possession of a firearm authorized for concealed or unconcealed carry upon the authority and license of another state is authorized to continue to carry a concealed or unconcealed firearm and license in this state; provided the license from the other state remains valid. The firearm must either be carried unconcealed and in plain view or fully concealed from detection and view, and upon coming in contact with any peace officer of this state, the person must disclose the fact that he or she is in possession of a concealed or unconcealed firearm pursuant to a valid concealed or unconcealed carry weapons permit or license issued in another state."
Transporting Firearms

Individuals with hunting licenses may open carry loaded long arms and handguns when hunting during hunting season. Outside of this and a few other limited exceptions, Open Carry of handguns in a public setting requires a valid carry permit. Carry of unloaded, cased firearms without a permit is allowed while on foot, just as it is allowed while traveling in a vehicle. Firearms that are not handguns, (long arms) carried by pedestrians generally must be both completely unloaded and cased.

However, any person eligible to legally possess firearms may openly carry unloaded firearms that are not cased specifically "When going to or from the person's private residence or vehicle or a vehicle in which the person is riding as a passenger to a place designated or authorized for firearms repairs or reconditioning, or for firearms trade, sale, or barter, or gunsmith, or hunting animals or fowl, or hunter safety course, or target shooting, or skeet or trap shooting or any recognized firearms activity or event and while in such places". Only under these circumstances may individuals carry unloaded firearms publicly that are not cased.

Generally, when carrying firearms in a motor vehicle, (when traveling on public land or roads) they must be out of reach of the driver, unloaded, and cased. Persons possessing a handgun carry license may carry a loaded handgun inside their vehicle on their person, just as they are permitted to do so on foot. Persons possessing a handgun carry license may transport a loaded handgun in a motor vehicle under their control, and store a loaded handgun in a locked, secure, motor vehicle. They may also transport loaded magazines for both handguns and long guns, however, they cannot legally transport loaded long guns. Firearms being improperly transported in any way may be immediately confiscated by police without compensation.
Carry on Private Property