I'm looking to have a gunsmith in another state do some work on my S&W X-frame, but I've never shipped a firearm anywhere. What do I need to do in order to ensure I ship it properly?

A box with his address on it...

Assuming the gunsmith is an FFL, then Jeepkid has it right - but I'll add, a handgun can't go USPS, it has to go FedEx/UPS or other carrier. Box it up, unmarked & not shaped like a gun, and ship it. Long guns can go USPS.

Personally, I don't ship mine in their original boxes, because even from the best smiths, sometimes not everything makes it back. I usually buy a cheap plastic handgun case and bed that into a standard shipping box with bubble wrap.

Update. An employee at my local hunting store said they could ship it, but the boss said no. So, I went to the newly opened UPS store in my town and asked them. They didn't think they'd be able to ship a handgun, but after a call to one of their higher ups who was more knowledgeable, they shipped it for me. The tracking number says it arrived today.

Sweet!

I personally don't tell them what it is...if they ask I say it's motorcycle parts.

a gun shop couldn;t ship it for you, unless they log the gun into there books, and then it would have to be shipped back to them, logged in and then back out to you for pick up, and MIGHT even require them to run a background check when they do give it back to you
as legally they cannot accept a gun and ship for you

UNLESS maybe they are a UPS shipping center and they are never knowing its a gun in the box?

But glad you got it there safely, now lets hope work gets done as you hope and makes it home safe and sound to you !

At has to go through a UPS hub, the outlet stores probably won't do it. I know I had to to go right to the UP garage. Some places can choose too. Maybe some hardware stores, if they sell guns.

The PIA is if no one is at your house to accept it. They try 2-3 times, and keep it a few more days, and then threaten to send back.

I know a dealer that routinely ships handguns USPS, BUT it is dealer to dealer, NOT from an individual to an FFL.

Your local hunting shop either isn't an FFL, or they're a moron. They could, however, have charged you transfer fees. But an FFL can ship firearms - it's absolutely foolish to do so on your part - but they can.