I'm a range officer at one of only two supervised public outdoor ranges in Idaho. Most of the issues we see are simply because we Idaho shooters don't know how to behave on a supervised range until we experience it a few times. Rules most frequently neglected:
1. actions open, magazines removed, chamber flag
2. bring case from back bench to firearm on shooting bench, not vice versa.
Latest most interesting incident to me was a fellow whose AR went full auto after he installed what he "thought" was a binary trigger. He also said he did "some work" on the FCG. His first few shots were semi auto, so whatever he did, his installation likely malfed. Told him he was technically in possession of an NFA rifle and he agreed, took out the defective FCG, and put away the rifle.