To get a better picture set up your camera on a tripod or if you don't have a tripod set it up with whatever and then use the timer so that you're not holding the camera when the picture is taken, also I've found getting some distance away and using my zoom lense keeps the auto-focus from focusing on the top of the barrel lug.
Steve

Approach life like you do a yellow light - RUN IT! (Gail T.)