Completely legal to ship long guns via the post office. According to both atf and post office regs.
One... dont tell anyone what you are shipping. And there is no reason they should even ask you.
I personally recommend just using their on-line click and ship option. You process the shipment and print the label. All you have to do is drop the package off or have the carrier pick it up.
They used to offer a discount for shipping this way, but they did away with it when the cost of stamps went down. All smoke and mirrors there.
