I've mailed a couple long rifles through my local post office recently. Only once had the person ask what was in the box, specifically if it was a centerfire long rifle. I said yes, and he then asked if I was an FFL or if it was shipping to an FFL. Told him I'm an individual shipping to an FFL. He took the package no problem and since hasn't question long packages I bring in to ship. I weigh and print the labels myself to avoid most of the questions, just drop it off and get the receipt. Never had an issue with USPS damaging a package, but I package the best I can with lots of bubble wrap and paper to fill the space.