How about this idea....
You want to own or buy guns and ammo, then you apply at the local Police Station/NRA Office/Gunshop, and have a Federal Background Check Card, valid for 5 years unless the conditions are violated. The local police keep a record of who has a currently valid card so they are aware if they have to deal with that person in a way that invalidates the card, that they can remove it for violation of the conditions. The conditions are already spelled out in the Gun Control Act of 1968.
Then whenever you want to trade, sell, buy, etc weapons, all you have to do is show your valid BG Check card and away you go. No card, no sale. This would prevent the whole private sale and trade show no BG checks loophole, and save gun owners money because they don't have to get a BG check every time they want to but a new gun, rather it's always sitting in their back pocket.