That's just what 'The 100' does. They like to put their characters in a position where no decision is the right one, you know? You have to kind of just hope that it works out.
I personally don't like guns at all, so pointing a gun at someone or having a gun pointed at me makes me feel very unbecoming. I think they're a scourge.
People who weren't there can say it was idiotic or shortsighted, but when you're in a moment where horrible things are happening in front of you, sometimes you just need to act on what's best.