Do you need to send your firearm through a FFL if you are sending it to a FFL gunsmith for repair/customization work? Can that gunsmith ship the firearm back to you or would it have to go throught a FFL for the return?
not for repair work. you can send it to the gunsmith directly and he can send it directly back to you. pay attention to how you send it. the ATF doesn't have a specific statement saying it has to be there next day air. if sending through an FFL, the FFL can send it through USPS in a flat rate box and it would be cheap. but if you're sending it yourself, UPS and FedEx has rules that say you have to let them know that a firearm is inside and it has to be sent 2nd Day Air or something like that. I typically let my FFL ship my firearms out. but they can send it directly back to you.
Long gun you can ship USPS, handguns have to go Fedex or UPS. FedEx and UPS, not federal or state law, require you to ship Next Day Air, over 21 Signature Required.
Cost about $50 one way. And you have to be home to receive the return package.
I'm at home now waiting for FedEx to deliver a pistol I sent back to the manufacture for repair.
Probably would have been cheaper for me to use a FFL. I'm out $50 for shipping, manufacture paid return shipping, and half a day work waiting on package.