I liked what I read, but I also found it a bit confusing... or maybe a better word would be abrupt. I think this could be a really excellent story if it was two or three times longer. Maybe start out with Frank pointing the gun and shooting and then go into a monologue in which the protagonist gives a bit of background information (like, is this a summer job or is he a student on an extended trip, something.)
I did enjoy the dialog though. ^_^