Can anyone tell me about this loophole at gun shows politicians keep referring to? I’d like to take advantage of this loophole, but don’t want to do anything illegal. Is it legal to buy a gun from another person without records of the purchase being kept on file somewhere?
You're lucky. I almost missed your question. The "gun show loophole" is buying from private sellers, i.e. not dealers with federal firearm licences, in states that allow them. Private sellers are just that. They don't want to keep the firearm anymore. They just want to sell it. Unless they are someone you trust, then you don't have a clue about how they acquired it or its history.
The opposition to it comes from the fact that requiring backround checks is potential de facto registration when firearm ownership is transferred with a federal NICS check, which some states require even between close relatives, although the feds are supposed to destroy the records of NICS checks. Is there any reason to trust the gubmint?