This booklet is the first of many planned works that provide instruction in the correct and safe methods of gunsmithing. In this treatise we discuss in detail Ackley Improved cartridges and how to headspace them correctly. Correctly headspacing Ackley Improved chambers will deliver better accuracy and allow the use of factory ammo from the parent cartridge to fireform, and in a pinch to save a hunting trip... It is imperative that the gunsmith whether hobby or professional learn to do the work correctly. If you need to learn how to install a barrel or chamber it look for our title; "Chambering Rifle Barrels for Accuracy" There are many books about gunsmithing and those that contain any great amount of technical information are long outdated. Still more of them are written by writers who have never made a living gunsmithing. All such books provide interesting information and some methods remain unchanged. However, as tools and technology change so does the process of gunsmithing. In many gunsmithing books subjects are spoken of in such a general way that the novice has a difficult time deciphering just what is intended. When you're learning a complicated process a clear understanding of the basics is equally as important as learning the nuances of advanced concepts. This booklet and those that will follow in the "Gunsmithing Student Handbook Series" are designed to be of value to gunsmiths at all skill levels.