I've learned my lesson. I'll gladly pay 'postage due' to get a machined carbine barrel back. I'm lucky this time that I had not done any work on the barrel blank being sent to me. And I hope the sender gets his money back. Flat Rate parcels are insured for $50 for free and for more if you pay extra. Well worth it, considering the alternative.
I have never had much luck collecting on postal ins. It is extremely time consuming and they like to argue. They want to keep ALL the money paid in for insurance. So they do their best to do just that.
Another little known aspect of this circus..lets say you have a claim as I did once..they broke the top of an antique tea pot that was insured for $350. They finally agreed to pay..but guess what they wanted to do with the teapot itself? DESTROY IT. I couldn't buy it..
So lets say you filed a claim on a broken rifle stock. Yup..they want to destroy the WHOLE item.