Can I send a stripped ar lower to an FFL dealer in another state by U.S. postal (priority).  Do I have to do anything special besides insurance and delivery conformation?
Thanks

You can send firearms other than handguns through the US mail.  This includes complete long guns (shotguns or rifles) in addition to stripped receivers or frames.  You can send it Priority or parcel post.

It must be declared to the postal worker as an unloaded firearm when you ship it.  There should be no marks on the packaging to indicate that it contains a firearm.

Insurance and delivery confirmation are good ideas, but not required by postal regulations.

Notification is not required as long as you are sending to a licensed dealer.  It is only required if you are sending to a non-licensee. (40CFR178.31(a))

How can a handgun be shipped?  One of my co-workers was wondering how to get a pistol shipped to his dad.

Handguns can be shipped FedEx, UPS, etc. You have to declare it's a handgun and many shippers are now requiring next day service. Generally handguns cannot be shipped via USPS. I would call the shipper to see what requirements are for that shipper. BTW, don't let them label it as containing a firearm.

the only way for a handgun to g othru USPS is FFL to FFL