IMO, it's a darn shame that society has made gun owner SO self-consious that they feel they MUST explain themselves at each/every turn.
Many honest people fell so ashamed that they might be doing something wrong, that they act shaky/spooky FTF with a clerk, sending up terrorist red flags.
longknife76 is 100% correct - As long as the shipper/mailer is acting legally, there is NO obligation to declare contents, except to answer truthfully the PO Clerk's 5 hazmat/fragile questions, and about insurance wants.
It is against Federal Law to label the exterior of any package as containing a firearm, BTW.
Unlike the common carriers (UPS/FEDEX/etc), USPS does not require package content descriptions when insuring or shipping - ANOTHER good reaon to use USPS.
FWIW, I usually break down all firearms, flintlocks included, into a smaller/shorter & differently-shaped package like a round or delta shipping tube - anything that doesn't look like it might be a firearm. (Out of sight/out of mind)
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