Requiem per un pistolero

There is one scene set an a campfire at night. At one point in the scene, one of the actors gets up and walks around behind the campfire and the other Cowboys sitting around it. As he does so, he bumps into the painted background and all of the distant mountains shake on the set.

This was the source of unending laughter in my high school film class in the spring of 1970. It is also the only thing I remember about this movie.

This is also notable as the last film performance of Raymond Hatton, who did over 500 movies starting back in the 1910s.