Hand guns are mailable if you are are an FFL holder. This is from the USPS rules for mailability.
Cheers,
Laurie
Exhibit 432.1
Mailability Requirements for Firearms
Unloaded Handgun
Handguns e.g., pistols, revolvers, and other firearms capable of being concealed on the person are nonmailable UNLESS mailed by a licensed manufacturer of firearms, or a licensed dealer of firearms, or an authorized agent of the federal government or government of a state, territory, or district, and ONLY when addressed to a person in one of the following categories for use in the persons official duties AND upon filing the required affidavit or certificate, as applicable (see DMM 601.11.1.37):
Addressee: Officer of Army, Coast Guard, Air Force, Navy, Marine Corps, or Organized Reserve Corps.
Affidavit or Certificate Requirements: Mailable with affidavit signed by addressee and certificate signed by the commanding officer.
Addressee: Officer of National Guard or militia of a state, territory, or district.
Affidavit or Certificate Requirements: Mailable with affidavit signed by addressee and certificate signed by the commanding officer.
Addressee: Officer of the federal government or a state, district, or territory whose official duty is to serve warrants of arrest or commitment.
Affidavit or Certificate Requirements: Mailable with affidavit signed by addressee and certificate signed by the head of the agency employing the addressee.
Addressee: Postal Service employees specifically authorized by the Chief Postal Inspector.
Affidavit or Certificate Requirements: Mailable with affidavit signed by addressee and certificate signed by the head of the agency employing the addressee.
Addressee: Officer or employee of a U.S. enforcement agency.
Affidavit or Certificate Requirements: Mailable with affidavit signed by addressee and certificate signed by the head of the agency employing the addressee.
Addressee: Watchman engaged in guarding federal, state, district, or territory property.
Affidavit or Certificate Requirements: Mailable with affidavit signed by addressee and certificate signed by chief clerk of department, bureau, or independent branch of the government agency employing the addressee.
Addressee: Purchasing agent or other designated member of an enforcement agency employing officers and personnel included in c, d, or e above.
Affidavit or Certificate Requirements: Mailable with affidavit signed by addressee and certificate signed by the head of agency stating the firearm is to be used by an officer or employee cited in c, d, or e above.
Addressee: Licensed manufacturers and dealers of firearms.
Affidavit or Certificate Requirements: Signed statement on PS Form 1508, Statement by Shipper of Firearms.
The mailer must be a licensed manufacturer or dealer mailing to another licensed manufacturer or dealer.
Handguns may be mailed without regard to the requirements noted in items ah if the addressee is the FBI (or its Director) or a scientific lab or crime detection bureau of any agency whose members are federal law enforcement officers, or state, district, or territory officers authorized to serve warrants of arrest or commitment.
Manufacturers or dealers must complete PS Form 1508, Statement by Shipper of Firearms, and file with the postmaster.
Postmasters may forward an unsatisfactory mailer statement to their PCSC for a ruling.
