The hot brass dance: it's not cute or funny, but it sure is dangerous
If you spend any amount of time shooting semiautomatic firearms, it's inevitable that you'll get some brass burns once in a while. Brass burns happen when an ejected cartridge casing (hot from the cartridge explosion and usually made of brass, but not always) makes contact with your bare skin. Sometimes, if you're really unlucky, the hot brass will stick to your skin and leave a bloody welt or blister. This happens most often with .22s, which are small and light enough to find their way into the most horrible places if you aren't careful. Ask Claude Werner, who has forgotten more about excellence in shooting than I'll learn in this lifetime. If it can happen to him, it can happen to anyone.
When your instructor advises you to wear a baseball cap or other brimmed hat on the range, this is why. Ideally, the ejected casings will rain down harmlessly on the bill of your hat instead of lodging themselves on your face or tumbling down the front of your shirt. Ideally. Reality isn't always ideal, however, and sometimes the bill of the cap actually reflects the casing directly downward if it hits the underside. Or sometimes the casing misses the hat entirely and falls down the back of your shirt, or rockets right up your sleeve, finding a comfortable resting place on the tender skin near your elbow. Fun times! But unless you wear a beekeeping suit while shooting, brass burns are just part and parcel of shooting semiautos.
We know from our lessons about basic range etiquette and the all-important Four Rules that as soon as your sights come off the target, your finger must come off the trigger. You must practice this over and over until it's second nature. It will take thousands of repetitions, which you can conveniently do with your empty gun (dry fire practice) or anything that has a trigger, whether it's a spray bottle or a cordless drill. But you must practice it, and it must become seamless and unthinking. That's called trigger discipline, and it's entirely not optional. We also know that we never point the gun at anything we aren't willing to destroy, and it must always be pointed in the safest possible direction. At a firing range, that means downrange (i.e. where the targets are)--and this rule must be followed always, no exceptions. Here's why:
This guy unwittingly demonstrated multiple failures of the Four Rules, which resulted in not one but two negligent discharges with what appears to be a clueless RSO standing directly behind him. Not only did he have poor trigger discipline, but his muzzle control was nonexistent. In his panic at feeling hot brass land down the back of his shirt, he fired two rounds directly into the crowd of people behind the firing line.
While the hot brass landing down the back of his shirt appears to be purely bad luck in this case, his incompetent gun handling may have resulted in someone getting gravely injured or killed. At the very least, it likely resulted in plenty of people vowing never to go to a public range ever again. Your responsibility to handle a gun safety doesn't end just because you're uncomfortable.
And that's really what it boils down to: very temporary discomfort. Will a hot casing leave a mark? Maybe, but probably not. Will it sting a bit? No worse than a mosquito bite or slight flick with a rubber band. Will it surprise and startle you? Only if you aren't ready for it. Brass burns are mostly preventable if you dress properly--this means closed-toe shoes, no deep V-neck shirts, no cleavage showing, no exposed midriffs, etc. Use common sense and consider not wearing your most revealing outfits to the range. Or prepare yourself for plenty of brass burns, whatever.
Ladies, I know you don't want to ruin your hair by wearing a hat--but would you rather ruin the skin on your beautiful face? I think not. And while I understand the feminine impulse to want to look cute, there's nothing sexy about dancing around in a panic trying to fish out the hot brass that just went down your bra while the crusty old range guys laugh at you. The firing range is not the place to try out your new deep-V blouse, okay? Besides, gun grease and gunpowder residue are really hard to get out of silk. Ask me how I know.
Don't be "that guy" at the range. If a hot casing gets in your clothes, carefully put your gun down on the bench rest (pointed downrange!) and then shake it out. By the time you get the casing out you'll probably realize it's not even hot anymore. The better thing to do is just...leave it be. It's really not that hot, and since you aren't stupid and you were expecting the possibility of a hot case hitting your skin at some point during your range session, you know that the temporary sting will be gone in seconds. Tough it out and then show off your cool new brass burns to your friends later on. Or if you're genuinely too sensitive to tough it out, for the love of pete, get that gun safely out of your hand and pointed downrange before you start hopping around like a weirdo.
Be brave, keep cool, and stay safe out there!