In most of the still free United States, private sales of goods between citizens, be they mules, lawn mowers, or guns, is perfectly legal.
The gun show "Loop-Hole" is just a political catch-word coined by Handgun Control, Inc., or the Brady Campaign? (I forget which) for a legal private sale of a firearm by the owner that occurred at a gun show instead of in a newspaper add, or a face to face meeting at a flea market, or something.
There is no "loop-Hole", as private sales of firearms between consenting individuals has never been regulated at a Federal level, ever.
It is up to this point in time at least, perfectly legal in all respects, unless it conflicts with local or state laws in your jurisdiction.
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