Michael: Greetings. Where to start. First, have your rifle checked by a competent smith to make sure it's safe to fire. Second, what type '03 is it? '03 or '03A3? Is it stock military or has someone "sporterized" it? Third, if safe to shoot, go out and sight it in at 50 or a 100m, with the ammunition you intend to use and see how it groups. Then, depending on the condition of the barrel, bedding, and a host of other factors, including your ability to shoot, you can figure where to start. You'd be best served by acquiring a book on the '03 providing you basic information with specifications and assembly/dis-assembly. Learn about your rifle first. Hope this helps, Dennis