Have you been able to read any of the "A Pilgrim's Journey" series of books by Mark Baker? I thought the scene where the rifle is loaded while on the run was hogwash, also. The author of the books, Mark Baker was the actor, Daniel Day Lewis's personal consultant on the film. He (Baker) states in his first volume of "A Pilgrim's Journey" on page 200 that Lewis wanted to learn to load and shoot on the run and that he practiced it until he could actually do it. Come to think of it, there was a show a few years back on the History Channel called "Conquest". It was hosted by the Englishman who played Cornwallis's Aide on "The Patriot". On one of the episodes of the show, he also demonstrated that it could be done.