Yeah, I have shipped handguns UPS to the original manufacturer for warranty work... I know that's legal, but you should see the look on the UPS employs face when they ask about the contents of the package.
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They all scramble to the back of the store to pow-wow with the manager while thumbing through procedural manuals.
I used to live on the GA/SC border and everyone I knew would regularly buy/sell long guns in person without giving it a second thought.
Strange thing here is that Ohio law specifically allows buying/selling of long guns with residents of bordering states with no mention of the federal prohibition... It's kinda misleading.