FWIW, I have heard of at least one airline, can't remember which one, tagging bags with guns for special handling. It doesn't say "firearms" or anything related, but the tags are used to ID bags containing high value items, which, BTW, still doesn't sound like a good idea to me. It sounds like a "Steal Me!" tag for anyone who knows what they mean.

Muss Muggins' post reminded of something, that could be beneficial for future travelers. My goal is to get to the airport a MINIMUM of 2 hours before my boarding time, with 3 hours my typical goal. Not always do-able, but the extra time can be useful if something unexpected comes up, like TSA's smartphone app saying the security wait time is 30 minutes but ends up actually taking over an hour (happened to me). Fortunately, my check-in was relatively hassle-free, with the airline's check-in attendant just asking to see the guns in their case and putting the orange tag on (the gun case, not the suitcase). It was easier than expected, especially since, like I mentioned earlier, it happened only 1-2 weeks after the FL airport shooting.