In accordance with SB 308, Leg. Act 2010 of The Georgia General Assembly, one may Carry any Weapon or LongGun in, on, or within: 1. Home, 2. Motor Vehicle, or 3. Place of Business; without a Weapons Carry License, per Georgia Code 16-11-126(a).
Furthermore, in accordance with 16-11-126(d) of the same Act, any Person who is eligible for a Weapons Carry License may transport a Weapon or LongGun in any Private Passenger Vehicle, provided; that whoever the Vehicle belongs to (in your situation: that of another), consents to the transpotaion of the Weapon of LongGun.
Unlike Wisonsin, if either of those two applies, then, there is no need to place the Weapon or LongGun in a Locked Case, unless you wish to rely on addtional exception under Georgia Law SB 308 16-11-126(c).
Unless I am mistaken, the Law Enforcement Officers Protection Act passed by Federal Congress may protect you further, if you are a Law Enforcement Officer. Addtionally, if that were true, then, you are exempted, completely, by Georgia Law 16-11-130(a)(1). [Ignore this if you are not a Governmental Offical.]
Either way..., Open Carry is Legal in Georgia, however; the practice, especially with LongGuns, is not well excepted in and around in The Metro-Atlanta area. Nonetheless, the letter of the Law prevails in the subject matter of Firearms in Georgia, as Georgia enjoys, similiar to Wisonsin, State-wide Firearms Preemption under Georgia Code 16-11-173.
Furthermore, unlike Wisconsin, in Georgia, Handguns are allowed in Restaurants that serve Alcohol, and in Bars as well..., provided; the Owner of the Bar consents, per Georgia Code 16-11-127(b)(6).
The exceptions provided under Georgia Codes 16-11-127(d)(1) through 16-11-127(d)(3) provide affirmative Defense to any Violation of Georgia Code 16-11-127(b). Under 16-11-127(b), Unathourized Locations for Firearms are: 1. Government Buildings, 2. CourtHouses, 3. Jails/Prisons, 4. State/Private-owned Mental Health Hospitals, and 5. Within 150 feet of any Election Place on Blue Law Voting Day.
Remember, though, if you can claim an exception under Georgia Code 16-11-130(a)(1), then, Georgia Code 16-11-127(b) does not apply to you. [Ignore this if you are not a Governmental Official.]