Sorry BillyBass, but your understanding of the subject is "fishy".

Things that get you on NCIS list of "Cannot Possess a Firearm".
Convicted of a Felony
Convicted of Domestic Violence - Gee......didn't that apply to this last guy?
Ever Renounced your Citizenship.
Unlawful user of or addicted to alcohol or drugs, including marijuana.
Been adjudicated Mentally Defective by a court of Law.
Dishonorable discharge - Gee......didn't that apply to this last guy, too?
Fugitive from Justice.
Subject to  Restraining order preventing your from stalking, harassing or threatening a domestic partner or child.
An alien Illegally or Unlawfully in the US.

further statistics....less than 1% of felons obtain their guns from a gun show.

The Social security rule was overturned because it did not allow for Due Process, AND the overturning was supported by the ACLU.
https://www.aclu.org/letter/aclu-endorses-hr-3516-social-security-beneficiary-2nd

GO FISH!