I have decided to embark on an exercise to pass along some of the knowledge I have gained over a 30+ years of reloading ammunition. I started loading shotgun ammunition in High School. I was introduced to metallic cartridge loading in College and have since gotten into casting bullets as well. I have read extensively on the topic of internal and external ballistics and have made my share of mistakes over the years. Yes, I have badly damaged one rifle (Ruger Mini-14) with handloads and learned much from that experience. I have had one ER visit due to stupidity on my part. I was old and experienced enough to know better but I let the stupid gene take hold for a moment. I will compose different chapters on different components but none can be expected to be comprehensive. Each is an overview of the particular component. Some of the readers will find portions simplistic and some may find the information overly complex. This following is for information and educational purposes only. Before reloading ammunition one must read at least one loading manual from a recognized publisher. Reloading is an inherently dangerous past time. Caution must be exercised in each step of the process. So, with out further ado, here is chapter one- Part 1. Primers. The primer is essentially a percussion cap that seats inside the head of the case. There are different type, size, grade, strength and color finishes of primers. There are two types of center-fire primers Boxer and Berdan. Boxer primers are what most US made ammunition is designed for. Boxer primers consist of three parts, the cup, the anvil and the priming compound. The cup is the part you can see on a loaded round of ammunition. Inside is a tripod shaped metal device called the anvil with the priming compound sandwiched in between. Boxer primed cases have one flash hole connecting the primer pocket with the body of the case where the powder is held. Berdan primers lack the anvil as there is a bump in the base of the case that serves as the anvil. Many European/Asian made cartridges utilize Berdan primers. Berdan primed cases have two flash holes. There are three sizes of primers. Large rifle, large pistol and small. Small rifle and small pistol primers are the same size but have some design and construction differences. All large primers are the same diameter. Large rifle primers are deeper than large pistol. There are three basic grades of primers. Standard, match (or bench rest) and military. Standard primers are intended for everyday ammunition. They have some degree of variance in thickness and flame intensity. Match or bench rest primers (different makers call them by different names) have a higher degree of quality control so each primer creates the same degree of flame as the others. Military primers have thicker cups and generally hotter flame temperature/intensity. There are two strength levels of primers, standard and magnum. Standard primers are for “normal” size and strength ammunition. Magnum primers are for very large capacity cases and or difficult to ignite powders. Primers come in two finishes, brass and nickel. There is no correlation between finish and the other differences. Large or small, rifle or pistol, standard, magnum or match can be brass or nickel. If you follow the recommendations of the loading manual you should be able to determine the primer best for your application. As different companies make primers to different specifications, any change of primer requires you reduce the powder charge and work up a new load. Reading primers. Reading primers in not really a science. It is more of an art. It is inexact and potentially dangerous for the novice When working up a load primers will normally display certain characteristics as the pressures near maximum pressures. The first sign is flattening. The rounded edges of the primer will begin to flatten and fill in. Next is cratering. The area around the firing pin/stiker indentation will be displaced upward. Finally is primer flow. Under extreme pressure metal will actually become fluid. The area around the firing pin/striker indentation will actually try to flow into the channel around the firing pin. The edges of the primer will fill in the primer pocket area so the base looks like one solid piece. When flow is observed, one can normally be assured the pressures are excessive and likely dangerous.