Happened to me yesterday. Ran into an old friend at the gun show, and he invited me to come shoot with him and his buddies in their secret spot out in the desert. My friend is an excellent gun handler. Of the two other guys, one is OK, the other is That Guy. He brought his .50 Barrett, his high-dollar AR15s and AR10s, a Nighthawk .45 and matching 9. Nightforce scopes, Leica rangefinder -- apparently he had plenty of money to spend on the best toys. He was in his 60s, so he was not a beginner. He was "experienced" - experienced at doing it wrong for many years. He had his finger all over the trigger, and "dangled" the pistol alongside when he was not shooting. I mentioned it to the friend who had invited me. He mentioned it to That Guy -- who then replied with the infamous Words Of The Fool: "It's not loaded." I will not shoot with anybody who says those words. First of all, yes it was. And second, whether they are loaded or unloaded, All Guns Are Always Loaded. The safe gunhandling rules apply to all guns; there is no Unloaded Gun exception.
I will not be going out with them again. My friend, sure. But if That Guy is going to be there, I'm not going to be there.