My experience with shipping USPS has generally shown poor handling of packages. Also I have had them ask what is in the packages. As to USPS in the ATF code they can't ship a rifle out of state to a un licsenced person. Your right though, they don't hire especially smart people at the counters. Beyond all I hate to lie about anything.
Pack it right to begin with and you won't have any problems, in my 32yrs of postal service,
THE number one cause of package loss/damage was irresponsible packing by the mailer!!!
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Read the regs concerning mailing long guns, as long as you're not transferring ownership, there's no reason to ship to an FFL, and the USPS cannot dictate as to the legality of shipping a rifle or shotgun.
Tim
http://www.usps.com/cpim/ftp/pubs/pub52.pdf432 Mailability
432.1 General
The following conditions apply:
a. Pistols, revolvers, and other firearms capable of being concealed on
the person (referred to as handguns) are nonmailable in the domestic
mail except as permitted in Exhibit 432.1 and DMM C024.1.0.
b. The disassembled parts of a handgun or other type of nonmailable
firearm that can be readily reassembled as a weapon are nonmailable
except as permitted in Exhibit 432.1 and DMM C024.1.0 or C024.2.0.
c. Unloaded antique firearms sent as curios or museum pieces are
generally permitted as specified in Exhibit 432.1 and DMM C024.2.0.
d. Unloaded rifles and shotguns may be mailed if the mailer fully complies
with the Gun Control Act of 1968 (Public Law 90-618) and 18 U.S.C.
921. The mailer may be required to establish, by opening the parcel or
by written certification, that the gun is unloaded and not excluded from
mailing because of the restrictions in 431.2b and c.432.3 Packaging and Marking
No markings of any kind that indicate the nature of the contents may be
placed on the outside wrapper or container of any mailpiece containing
firearms. Mailable matter must be properly and securely packaged within the
general packaging requirements in DMM C010.
433 Mailer Responsibility
Even though certain types of firearms are permitted to be mailed within the
provisions of the postal law in 18 U.S.C. 1715, it is the mailer’s responsibility
to comply with all federal and state regulations and local ordinances affecting
the movement of firearms.
434 Legal Opinions on Mailing Firearms
Postmasters are not authorized to give opinions on the legality of any
shipment of rifles or shotguns. Mailers should be referred to the nearest
regional ATF office for further advice. See 435 and Exhibit 435.