I'm usually a live-and-let-live person and just let stuff be, but I would have gone to the range officer about that guy. The two indoor ranges in my neck of the woods are pretty heavily monitored, and they're pretty good about getting on the PA and yelling at people when they need to. Too bad your range staff weren't being more vigilant. If I ran a range, I'd require everyone to demonstrate to me that they could fully operate the weapon before they took it out onto the range. To do otherwise is just irresponsible on the range's part. And as you experienced, dangerous.
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