[Xringshooter]

Sharontony,
You stated "...hypothetically one could sell a gun to a friend without going thru an FFL, and years down the road if it somehow came back to them, there is no way to prove the transaction didn't happen "by the book". You might say the two would be asked to ID the FFL they went thru, but what if they don't recall? Not remembering isn't a crime, and you're innocent until proven guilty, not the other way around..."

That's fine if you and the buddy remember your stories exactly. The police (or BATFE or someone else) probably won't be questioning you both at the same time. Most likely buddy would say "Oh, I got this from XYZ, x years ago." Police would say "what FFL did you go through?" By this time buddy is getting nervous, can't recall what you and he discussed and will probably tell the truth "Well, we didn't actually go through a FFL because XYZ said ***" then the SWHTF.

If you're going to do a long term loan, jot it down and you and buddy keep it with your other valuable papers. Then, if questioned, the note will show the details. If your going to sell it to buddy just go to a FFL and do that way, then there's less chance of problems in the future if something happens.