GPS- I have NOT YET done it but that was my understanding. On my bucket list is a trip to Alaska "My Way" which means knocking around in the bush, etc. and I bought a stainless steel Ruger Bisley 454 Casull for bear protection. I was told the post office would ship it to Alaska and then I pick it up there. I don't think you can take a firearm into an airport- check the law.
BTW- really like the 454 Casull.
"You" cannot mail a handgun via the USPS.
May a nonlicensee ship a firearm through the U.S. Postal Service?
A nonlicensee may not transfer a firearm to a non-licensed resident of another state. A nonlicensee may mail a shotgun or rifle to a resident of their own state or to a licensee in any state.
The U.S. Postal Service recommends that long guns be sent by registered mail and that no marking of any kind which would indicate the nature of the contents be placed on the outside of any parcel containing firearms.
Handguns are not mailable. A common or contract carrier must be used to ship a handgun.
One source concerning transporting firearms...
TSA - Transporting Firearms and Ammunition