With the sole exception of INHERITANCE- any transfer of ownership of a firearm across a state line MUST be made thru a FFL in the destination state. Includes sales, gifts, raffles, giveaways, etc ad infinitum.
This is covered in Federal law under Title 18, US Code, section 922. By the letter of the law, the firearm must go TO a FFL in your state of residence. You receive it from them after doing a 4473 and a background check.
An inherited firearm may be sent directly to the recipient by the executor, so long as possession is legal in the receiving state. Same law.
If your bud is not a FFL, he will have to use UPS or FedEx Next Day Air, and it will bite him for about $70 in shipping. However, if he can find a friendly dealer at his end, the dealer CAN use US Mail (only dealers and mfgrs can MAIL a handgun). That is usually a LOT cheaper. Priority mail flat rate box.