You are a California resident. Your vehicle is registered in California. You vote in California. Owning property in another state doesn't change that.
I seriously doubt that you could buy a gun in Florida other than from an individual who is not a dealer. If you can't vote in Florida, you are just another visitor. However, there would be no problem with buying magazines.
And yes, ONE of those two states has to be your primary state of residence. Sounds to me like it's CA.
You both are incorrect.
If you own a house in Florida, during the time that you are staying in that house, you are a resident of the Florida. If a person maintains a home in 2 States and resides in both States for certain periods of the year, he or she may, during the period of time the person actually resides in a particular State, purchase a handgun in that State. However, simply owning property in another State does not qualify the person to purchase a handgun in that State.
27 CFR 478.11 Scrolll down to page 8, left hand column and see the definition of "State of residence."
The following are examples that illustrate this definition:
Example 1. A maintains a home in State X.
A travels to State Y on a hunting, fishing, business, or other type of trip. A does not become a resident of State Y by reason of such trip.
Example 2. A is a U.S. citizen and maintains a home in State X and a home in State Y. A resides in State X except for weekends or the summer months of the year and in State Y for the weekends or the summer months of the year. During the time that A actually resides in State X, A is a resident of State X, and during the time that A actually resides in State Y, A is a resident of State Y.
The example in the actual text of the law states that the person who stays in his second home on the weekends is still considered to be a resident during those periods when he resides in that home. the CFR says that if you MAINTAIN a home in a state, you are considered to be a resident of that state during the time that you are staying in the home that you maintain. Since we here in Florida have a large snowbird population, that covers them quite well. (27CFR478.11)
The question would be what does it mean to maintain a home? The CFR gives some guidance on that. It specifically says that a person who owns property (like a hunting cabin) is not maintaining a home. Likewise, renting a timeshare would not be maintaining a home. The CFR does say that a person who has a home that he only stays in on the weekends and the summer would be a resident during the time he is in that vacation home, therefore a person in the situation described by the OP would not be breaking the law by purchasing a handgun or a long gun while he is here, whether that is face to face, or through a dealer, as the regulation clearly considers him to be a resident.
The problem comes when you go to prove your residency to the dealer. The regulation states that the proof of residency must be a government issued identification that has your name, DOB, and address on it, or any combination of government issued documents that state those items of information. In the OP's case, a DL from his other state and a tax notice from the tax assessor's office may be sufficient, but a state ID or CCw would be easiest and present the least hassle. Since you are not required to present such ID in a FTF transaction, you could do that legally without even having an ID, as long as you maintain a home in the state.
However, a state ID (or CCW) with a Florida address on it does not make you a resident, as you can obtain those without proving that you are a resident. Residency is the key.
Under the aforementioned law, the original poster is a resident during the times in which he is staying in his Florida home and can thus purchase weapons here. Whether or not CA will allow you to import your guns is a different matter which I cannot help you with.
