girls, if you actually own a flare gun, then you should also own expired flares after three years or less. And you really need to practice using the flare gun, if for no other reason that to see how puny and ineffective any non-SOLAS flare is.
So don't ask what flares can do, take an expired one, fire it up into the sky to see how it works. It will usually work even if it is ten years expired. Now take one and fire it at something you want to "kill". Don't be surprised if it bounces off and doesn't impress anyone.
There must be video already up on utube.