Under federal law, buying a firearm as a gift is perfectly legal.
- Person A purchases firearm with his or her own money.
- Person A fills out Form 4473 as the actual purchaser.
- Person A transfers firearm to Person B*.
(*The transfer must still comply with state and federal law. Those requirements will vary depending on the residence of A and B.)
Straw purchases can occur even when both parties are non-prohibited, but as long as Person A is the actual purchaser and actually giving a gift, it's fine.