I don't believe USPS will accept handguns from non-FFL but not sure.
Per federal law, operational handguns can't be sent via USPS. Common carrier only, and IIRC, only overnight shipping.
I'm a FFL and ship USPS regularly without problems.
Steve
Yep. FFLs can ship handguns via USPS.
The overnight restrictions on other carriers are the companies requirements to make it harder for their employees to steal packages containing handguns. The restrictions have nothing to do with ant federal law.