Also: I have a financial interest in the local indoor range and I lent a revolver to them as a rental firearm until they got a replacement in the same caliber. Now that the replacement is in and I am looking at getting my firearm back, do we need to perform a transfer across state lines? I have sent pistols back through the local tri-state outfitters and they haven't performed an FFL transfer since the firearm never changed ownership. Since the firearm at the range was never up for sale per se, is a transfer required?
If they logged it into their acquisition and disposition book ("bound book"), then they have to show who it goes to when it leaves their possession. That will have to be someone who resides in their state or another FFL. It may also depend on how they characterized recieving the revolver. They may be able to return it directly to you if they had it for "repair," for example. Talk to them (the FFL in Idaho who has the gun at the moment) about it. It's their recordkeeping and FFL that is at stake.