No worries. Was just thinking that from this description, which sounds to me like a static electricity problem: ... another soldier, on his way to the ref

No worries. Was just thinking that from this description, which sounds to me like a static electricity problem: ... another soldier, on his way to the refrigerator, tried to squeeze past him. That’s when their gun holsters made contact. “All I remember was the clanking” of the two holsters, the sergeant would later tell an Army investigator, according to a military report, “and [the] gun shot.” As for "how?", I clearly have no idea. :)