majormadmax
Úlfhéðnar
Under Federal law, an unlicensed individual is prohibited from transferring a firearm to an individual who does not reside in the State where the transferee resides. Generally, for a person to lawfully transfer a firearm to an unlicensed person who resides out of State, the firearm must be shipped to a Federal Firearms Licensee (FFL) within the recipient’s State of residence. He or she may then receive the firearm from the FFL upon completion of an ATF Form 4473 and a NICS background check.
In regard to transferring firearms between individuals residing in the same state, any person may sell a firearm to an unlicensed resident of the State where he resides as long as he or she does not know or have reasonable cause to believe the person is prohibited from receiving or possessing firearms under Federal law. Please note that there may be State and local laws that regulate firearm transactions. Any person considering acquiring or transferring a firearm should contact his or her State Attorney General’s Office to inquire about the laws and possible State or local firearms restrictions. A list of State Attorney General contact numbers may be found at http://www.naag.org/.
Most Frequently Asked Firearms Questions and Answers - ATF
https://www.atf.gov/resource-center/docs/0813-firearms-top-12-qaspdf/download
Note: handguns and other concealable firearms are not mailable through the United States Postal Service and must be shipped via private common or contract carrier (18 U.S.C. § 1715).
So yes, he could ship (via common courier, and not USPS) a firearm to you if both of you are in the same state.
How much you will trust a seller to do so depends on a variety of variables. It's your call based on how comfortable you feel with it (and how much money you are willing to "gamble" on it).