First, don't put your guns in checked luggage. Call the airline and get instructions for transporting a handgun. Some airlines will have a different place to check the gun, depending on carrier and airport.
Second, NJ does not prohibit out of state residents from entering the state with their handgun... even just to shoot at a range. NJ does not recognize any CCW reciprocity or even concealed carry by the average state resident. All handgun owners must lock the firearms, each in it's own container, unloaded. You must have a copy of your NY license as well. Do not mix several peoples' handguns in the same checked baggage.
The definitive source for this would be Anthony Colandro at Gun-For-Hire in NJ www.GunForHire.com. I would call him for advice.
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