Theater I Think...
Did a firearms training course outside Las Vegas 2 years ago. Fired at least 400 rounds of ammunition (.45ACP) that day. Drove to McCarren Airport right after finishing the course in order to make a 7pm flight so no time to shower, change clothes etc.
Going thru TSA, I get swapped. My first thought is "Uh-oh", not good )-:
So what does the swap strip detect...NOTHING! If ever it should have registered as positive, I would think it would have been that day.