Wildcat Cartridges: Reloaders Handbook of Wildcat Cartridge Design

By Fred Zeglin and Wayne van Zwoll

The Reloader's Handbook of Wildcat Cartridge Design is a must have for all shooters regardless of their experience. For the hunter with one gun or collector with many, you will find valuable information on accuracy, designing, building, loading and shooting wildcats. Calibers start with the tiny .10 ranging to some brawny .50 calibers; there is something for every interest.

Self reliant shooters and gunsmiths will learn how to make their own reamers and reloading dies in this book. Time and money are both saved when you make your own tools. If you desire to try out a new cartridge design you can be testing the new design in a day or two instead of weeks or months.

Dimensioned drawings and loading data accompany cartridge descriptions. Historical cartridges as well as the newest and most popular designs are included. Chapters about important cartridge designers like P.O. Ackley, Jerry Gebby, Rocky Gibbs, and Charles Newton are important resources for the reloader and shooter alike.

Publisher Larry Root says, "After 15 years and nearly 30 titles as a publisher, I have found this book a great project with new and useful information rather than a rehashed often incorrect and untested writing that seems so common today. "

"Fred has illustrated his book well, with neat line drawings and photos you probably won’t find anywhere else. It’s a rare technical treatise that draws you in with illustration, or that keeps you with an easy flow of chat that, were it lifted from print, might pop up at any gun counter or handloading bench. Fred Zeglin has done well with this book, giving wildcatters – indeed, all rifle enthusiasts – an overview of a culture often mentioned but little explored on the page." Wayne van Zwoll

"For anyone interested in wildcat cartridges, this is a "must have" book. It's thorough, and it's up to date." Larry S. Sterett, Gun Week

"One of the problems collectors often encounter when they purchase custom-made sporting rifles is the absence of commercially made ammunition for those arms... This book offers hope to just those collectors.

Written by a professional gunsmith and cartridge maker, it examines the history of "wildcat cartridge" development. In addition to discussing vintage designs, such as those developed by P.O. Ackley, Jerry Gebby, and Charles Newton, the book covers more recent work carried out by Estergaard, Gibbs, Z-Hat, and more." Herbert G. Houze, Man at Arms Magazine, Vol. 28, No. 4, 2006

"This is a fantastic book on American wildcats, US loads and much more. A must have for wildcatters and gunsmiths." Big Bore Journal, No. 18, June 2006

• Language: English
• Publisher: Z-Hat Publishing
• Release date: Mar 12, 2022
• ISBN: 9780983159810

Book preview

INTRODUCTION

Did you ever wonder at what point a shooter crosses the line and becomes a Gun Nut? Most wives would argue that the crossings over takes place somewhere between the acquisition of the second and third firearm, then you’re an official Gun Nut.

Another obvious definition of a gun nut is; when the mild mannered gun enthusiast is overcome with an uncontrollable urge to design a cartridge all his own. In other words, if you are reading this you have in all likelihood, already crossed that line, becoming a certified Gun Nut. Welcome to the crowd!

The purpose of The Reloader’s Handbook of Wildcat Cartridge Design is to help the would-be cartridge designer along the path to success. No other book has ever provided the reader with the necessary information to properly design a new wildcat cartridge. In these pages you will find dimensions, and information that literally took years to assemble in a useful form. Even if your not planning to design your own wildcat the information is this volume will be invaluable to your reloading and shooting experiences.

Every effort was made to collect accurate information for this book. In many cases the original or at least the earliest published data was used to insure correct information is provided. The author preferred to spend more time locating details to repeating long standing errors found in earlier works. With all that said there are likely still errors in this book, human hands assembled it after all.

Reloading is a hobby which offers the gun nut a way to spend numerous additional hours with his favorite rifle, or newest toy. Wildcatting extends that hobby even farther. When you begin loading for a new wildcat with no published load data available, it takes long hours of careful testing, and provides for long hours of enjoyment as you prove out your cartridge. Hopefully this book will help gun nuts everywhere to discover exciting new territory in the hobbies of shooting and reloading.

Here’s to many happy days a field and at the bench!

CHAPTER 1

What is a Wildcat?

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Good Question. In gunsmithing terms a wildcat is any cartridge that is not now a factory offered caliber. Occasionally cartridges make the jump from wildcat to a factory offering. In rare cases cartridges that were once factory offerings become wildcats when the factory drops them, but they hang onto or later develop a following. In other words, there is no factory source for their brass or ammo.

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A1 Miller in Wildcat Cartridges offered another definition of wildcatting. He said, Exactly when the terms, wildcat cartridge and wildcatting were first applied and who applied them is anybody’s guess- but the practice is as old as the metallic cartridge itself. Basically, the history of cartridge development is the history of wildcatting. From the very beginning, ballisticians, military ordnance experts, gunmakers, and others interested in improving small arms ammunition based their experiments on their predecessors’ success. Each military or commercial cartridge introduced served as a point of departure, spurring improvements, not only in case shape and bullet construction but in primers and propellants as well.

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In the simplest explanation, wildcats are an opportunity for gun nuts to express themselves, ballistically. Every gun nut has a pet caliber, or pet project that they wonder (often allowed) Why doesn’t the factory do this, it’s so obvious! The truth is that in many cases these pet projects would have appeal to a limited number of shooters and therefore are not likely to attract the attention of the big factories. On the other hand there can easily be enough interest to keep an individual custom shop busy.

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Wildcat all the way.

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Cartridges that fall into this category have never been factory cartridges, and probably never will. There are many reasons why a wildcat will not attract the factories as a new production cartridge. First and foremost is marketability, the factories want a cartridge with pretty broad appeal, often wildcats are specialized cartridges that attract a relatively small portion of the shooting public. The second most important reason factories avoid wildcat designs is for mechanical reasons. Cases with sharp shoulders and minimum body taper do not fit well with the methods factories like to use for chambering and production of ammunition.

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Modem production ammunition tends to run close to the minimum specifications allowed by The Sporting Arms and Ammunition Manufacturers' Institute (SAAMI). Factory Chambers tend to run toward the maximum limits of SAAMI specifications. This system works extremely well with cases with shoulder angles of 30 degrees or less and a fair amount of body taper; it’s a forgiving combination. This has become so pervasive in the industry that shooters frequently have concerns about how the web of the case is swelling when fired in their gun; the cause is minimum dimension brass. Cases designed with minimum body taper and shoulders sharper than 30 degrees must be held to closer dimensions, so they become more expensive in a production atmosphere.

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Wildcat to Factory.

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An example of a wildcat becoming a factory cartridge is the 243 Rockchucker; it was the most popular of the 243/6mm wildcats available, prior to Remington introducing the 244 Remington in 1955.

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The original Rockchucker was based on the 7x57 case necked to 243, with a 32-degree shoulder. Remington chose a 26-degree shoulder for the 244. In the same year, 1955, Winchester introduced the 243 Winchester with it’s 20- degree shoulder as a factory answer to the popularity of the 243/6mm wildcats that were thriving at the time, this along with Remington’s offering spelled death for the 243 Rockchucker, although there are still people shooting that wildcat today. (Barnes, Frank C. Cartridges of the World. 3rd edition. (C) 1972.)

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Some wildcat cartridges break this rule of no factory production, through no fault of their own. The 35 Whelen was a wildcat for about 75 years before Remington decided to standardize it in 1987. Unfortunately, this can damage the reputation of a cartridge. In the case of the 35 Whelen the ammunition that is factory loaded for it today produces relatively low velocity by reloading standards, some reloaders say, You could use a sun dial instead of a chronograph on such loads.

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Of course that’s an exaggeration, but Remington publishes their factory load for the 35 Whelen with a 250 gr. bullet at, 2400 FPS. A quick check of published loading data revealed numerous listings for the same weight bullet over 2500 FPS. That is not to say you should jump straight to that level in your gun, use appropriate testing methods, see Chapter 17.

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These factory loadings some would call anemic are designed for two totally valid reasons, first to accommodate the fact that the most recent factory gun manufactured in 35 Whelen was a pump action, a relatively weak design when compared to modern bolt guns. The second reason is that many of the guns built in this caliber over the past 75 or so years are of questionable strength. Headspace may vary some on these wildcat rifles built over the years. By offering low pressure ammo the manufacturer minimizes liability. A well-built modern commercial bolt-action rifle will handle substantially higher pressure and therefore give much better ballistics. Still reloaders should use common sense, if the 30-06 is loaded to 60,000 PSI according to an Oehler Model 43 then any variant of the 06 case is limited to the same factory pressure. Since the Oehler system is limited by its design and cannot tell you the precise correct pressure for any given load it is used as a comparative tool. Where factory ammo is available you can use it as a standard, if you never exceed factory pressure you should be within safe limits.

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Another example of a wildcat finding its way into factory production is the 300 Remington Ultra Mag, which arrived in 1999, soon followed by its brethren.

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Popular wildcats preceded the Ultra Mag in the market place, North American Shooting Systems and Dakota Arms both offered their own cartridges based on the 404 Jeffrey case; the 300 Canadian Magnum, and the 300 Dakota respectively. Some would argue that the Dakota offerings are not wildcats, however, since they are only available in semi-custom, or custom built firearms it is safe to call them wildcats.

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Heavy Express was a group of wildcats based on the 348 Winchester case with the rim modified to a rimless design, comparing it to the 300 WSM it’s not hard to see the similarity.

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Factory to Wildcat

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Charles Newton had a great idea for a line of cartridges in the first decade of the twentieth century. Newton was many decades ahead of his time; he designed the first high velocity commercial cartridges. The most famous of which are the 256 Newton and the 30 Newton.

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Newton succeeded in convincing more than one ammunition manufacture to produce ammunition for his cartridges. The reasons for his failure as a firearms maker are varied.

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Apparently, he was a genius as an engineer and ballistician, but lacked good business acumen. As a result the rifles produced under his name were diverse in quality, from beautiful well-built rifles to cheap junk that will put any business under. Newton also built very lightweight rifles for his cartridges, which have respectable recoil (especially the 30 and 35 Newton), this only added to the marketing problems. Eventually the reputation for heavy recoil and questionable quality rifles killed the company and ammunition makers dropped the ammo from their lines.

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Newton’s cartridges are good designs even by today’s standards, but they are relegated to wildcat status, by the lack of available factory brass. For more details see chapter 19.

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Modern Wildcats...

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Wildcatters these days seem willing to spend far more than in the past on their pet cartridge. One example of this is the 470 Mbogo. This cartridge is based on the 416 Rigby case.

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The designer has a web site devoted to this cartridge with a surprising amount of information about the development and loading of the 470 Mbogo. Not to mention the story of its first major field test in Africa.

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The web address as of this writing is: http://www.470mbogo .com unusual effort by the designer went into making correctly head stamped brass for the 470 Mbogo. The designer, Dave Estergaard had a bunter made (the stamping tool used to put the headstamp on the brass). Not many wildcatters go to this extreme for their baby.

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The 19 Calhoon and 19-223 Calhoon are examples of cartridges born out of one mans interest in a challenge and his abilities as a designer. James Leahy well known for his Calhoon bullets, was looking over the results of the 1970’s NATO ammunition trials. He noted that the British had entered a 4.85mm cartridge in the competition and it had faired very well. Unfortunately for this .19 caliber offering, that was the same trials where the Germans offered the SS109 loading for the 5.56mm NATO. When all was said and done the 4.85mm had performed well but the difference between it and the SS109 were not enough to convince NATO to change to a new cartridge, which would have necessitated either rebarreling all the 5.56mm guns in the arsenal or replacing them with new guns in the 4.85mm.

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Leahy saw in the test results some interesting data. The .19 caliber offered superior sectional density with ballistic coefficients similar to the .22 caliber. Add to that the velocities, which approach the 220 Swift with far less powder, and therefore longer barrel life and less recoil. Two cartridges emerged from Calhoon’s efforts; the 19 Calhoon is a 22 Hornet necked to .19 with the shoulder blown out to 30 degrees and the body taper at minimum. This little darling will send a 27-grain bullet down range at 3600 feet per second (fps). The 19-223 Calhoon will send a 32-grain bullet out at 4100 fps, and a 44- grain bullet at 3600 fps. While Leahy did not invent the .19 caliber bore he saw a missed opportunity and developed some respectable cartridges to fill the niche.

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Hawk Cartridges are a line of wildcats, eleven in total. Originated by Robert Fulton of Hawk Bullet fame in 1988, Bob started with a 375-06 Improved and was not satisfied with the results. He attempted several variations on the chambering until he finally had a case with minimum body taper and the shoulder moved forward. When he was done the 375 Hawk (so named for his company) had about 9% more case capacity than the parent 30-06 cartridge he had started from.

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Trends in the industry at the time were toward large capacity magnum cartridges. As a result some shooters began to see that big muzzle blast, heavy recoil, and belted cases left something to be desired. In effect, a market for cartridges with moderate case capacity and decent ballistics was created by the factories moving toward large capacity cases. In 1995 a client, Graydon Snapp, introduced the author to the 375 Hawk/Scovill and Bob Fulton. It was just a few months later that the whole fine of cartridges was developed around Bob’s original work, with his blessings. The Calibers range from .240 to .411 and offer something for nearly every shooter or hunter. Success for the Hawk line came from the fact that they filled a niche in the market, low recoil, magnum velocities, no belt, they work in a standard length action, and inexpensive common brass can be used to form them.

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That gives you three examples of successful wildcats; note they represent three totally different ways of looking at wildcats. The cartridges can be used for anything from small varmints on up to Cape buffalo. Availability of brass, bullets, barrels, actions, and accessories has expanded greatly; today there is more to choose from than ever before. Consequently, new wildcats are inevitable. You’re only limited by your imagination.

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Why bother?

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This is the second most common question concerning wildcat cartridges, Why bother? Well, there are as many excuses as there are wildcats. Like most excuses, some are good, some are not so good, and some outright stink.

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The best excuses are those that involve a new combination of a specific firearm and a caliber that the factory will not produce any time soon or more likely never produce at all. Look back at our earlier examples to see what the excuses for those wildcats were. The 243 Rockchucker came about in the years following World War II. In those days the factories did not build rifles or ammunition for 243/6mm cartridge in the United States.

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During the 1920s the British worked with a number of 6mm cartridges. In the early 20’s Holland & Holland introduced the 240 Magnum Rimless, also know as Holland’s 240 Apex.

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At the same time, Holland introduced a rimmed version of the cartridge, which of course is the 240 Magnum Flanged. These cartridges boasted a 100 gr. bullet at 2900 feet per second (fps), in the factory loadings. In 1923, Kynoch, in conjunction with Manton & Co. introduced the 242 Rimless Nitro Express, originally marketed as the 242 Manton. Factory data indicates that this cartridge would push a 100 gr. pill at 2800 fps.

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Earliest of all 6mm cartridges came from the Germans. All the way back to about 1895, the 6x57 Mauser was the earliest know commercial endeavor into the 6mm bore. As the name indicates the 6x57 is based on the 7x57, which was first introduced in 1893.

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Now back to the U.S. Factories on this side of the ocean largely ignored small calibers with few exceptions, until the end of World War II. The 6mm Lee Navy, originated in 1895 was one notable entry from this side of the ocean. The last factory ammo for this caliber was probably made around 1939. The most successful of the prewar small caliber cartridges is the 220 Swift, still in production today.

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Following World War II gun folks found themselves in a unique position. With the post war economy people had more time for leisure, so hobbies were on the grow, including hunting, shooting, and reloading.

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During the war years it was necessary for shooters to learn to make do with what was available. As a result many gunsmiths had learned to make tools, reloading equipment, and even bullets. One such person was Fred T. Huntington. Fred became an expert at making dies and of course started RCBS. On a visit to Huntington’s in Oroville California in 1983 Mr. Huntington took the time to show our group some bullet making dies that he had made in the 1940’s. A customer had donated them back to Mr. Huntington for display in his store. Fred talked about the tools he had designed and the reasons they were necessary at the time.

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In those post war days military surplus powder became available, and not long after commercial powders followed. For the first time reloaders had a choice of powders which would allow for more experimentation. Prior to the war, the gunpowders available were not capable of delivering the burning characteristics that cartridges smaller than .308 need to perform at their best. Armed with these new powders Mr. Huntington and many other wildcatters developed several new wildcats, among the most successful was the 243 Rockchucker.

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At the time Fred Huntington developed the 243 Rockchucker, there was little in the way of competing cartridges on the market. The correct time and place had come together for the 243 Rockchucker to become a success. Gunpowder by that time was available to deliver good ballistics. Not to mention the 257 Roberts was popular, so the interest in smaller bores was present, ready to be exploited. In the case of the Rockchucker, the cartridge actually filled a niche for the shooting public.

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It would be several years before Remington and Winchester recognize the opportunity the 6mm bore offered them for marketing.

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Now lets bring this full circle... Why bother?

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First, to fill a perceived need. Second, to take advantage of changes in technology, whether it is in firearms, brass, or other components. Third, you see a combination of a gun and a caliber that would work well together for a specific purpose. Finally, just because it’s fun.

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Who can design a wildcat?

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Anybody who has the desire and the wherewithall (is that a word?) can design a wildcat cartridge. Designing a wildcat is a way of having something that no one else in the whole world has. It's a challenge to work out the details. It’s interesting to try to design a cartridge that will do something that no other cartridge will do in that same way. Wildcatting is just plain fun, and is the natural full embrace of your shooting hobby.

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What do you need to design a wildcat?

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Nothing, well almost nothing. You need a goal, what niche do you want your cartridge to fill? Then you need some basic knowledge, what type of firearm will work with your wildcat? Seek advice from a competent gunsmith, keep in mind that not all gunsmiths are experienced wildcatters.

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A chamber reamer will have to be made to meet your needs. Then a test gun is built, its OK to make it a nice gun because even if the wildcat turns out to be less than you expected you can rebarrel it to something else, no one will ever know but you.

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Then you will have to work up loads this can take a lot of time; with a true wildcat there is no reloading manual to follow (some manuals contain data for the more popular wildcats). It is exciting to test a new wildcat and get more than you bargained for.

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There are now some easy to use software products that can help you design the cartridge of your dreams. RCBS.Load contains a Cartridge Designer which is simple to use, and future releases will contain a load estimator. Then Quick Design, from Neco is another product that will be useful to the wildcatter for designing the cartridge. The advantage to these software products being used for design is that they will provide information instantly that you would spend a fair amount of time calculating. For instance, case capacity, and in the case of Quick Design it will import data directly into Quick Load, the internal ballistics software from Neco. More on Software later, see Chapter 8.

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Welcome to the wonderful world of Wildcatting!

CHAPTER 2

Whatchamacallit...

or Nomenclature (What’s the correct name for that thingamabob?)

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Widgets, whogeewhats, and thingamajigs are commonplace in conversation. But, to tell the truth it seems no two of these figurative items is ever the same when pointed out. That’s because words mean things. The words above are used when we can’t think of the correct name or simply as a placeholder in the conversation so we can concentrate on the concept rather than a specific product or item. So what does this all have to do with wildcatting? Again, words mean things; we have names for cartridge components and they serve to allow for concise and specific communication in an article, discussion, or written report. Below is a collection of terms that reloaders and wildcatters will often use, along with diagrams to display and name the various parts or cases and bullets.

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Action: The portion of the firearm which performs the action of handling and firing the ammunition.

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Bell: To flair a case mouth to receive a bullet easily.

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Bolt Face: Forward face of the bolt which rests against the back of the cartridge when the firearm in loaded. Also called the breech face.

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Bullet: A projectile formed from various metals such as lead, copper, or bronze. They may be homogenous or an amalgamation of various metals.

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Bullet Swaging: To form a bullet in a die.

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Caliber:

Approximate diameter of the bullet or gun bore.

A specific cartridge design, i.e. 30-06 is one caliber, 25-06 is another.

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Cannelure: One or more grooves cut or rolled into the circumference of the bullet where the crimped case mouth can grip the bullet.

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Cartridge: A completely loaded ready to fire piece of ammunition.

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Case: A metal cylindrical container that holds the primer, powder and bullet. Also called brass.

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Case Forming: To form cases for one cartridge case from a different case.

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Case Head: Solid portion of the case at the breech end. Also called the base of the case.

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Chamber: Breech end of the guns bore which receives and supports the cartridge for firing.

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Chamber Reamer: Same as finish reamer.

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Chamfer: To ream or bevel the case mouth, primarily inside.

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Chronograph: An instrument used to measure velocity of a bullet.

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Components: The parts which make up a cartridge.

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Crimp: To bend inward the mouth of the case to grip the bullet. Used only with bullets having a cannelure or crimping grove.

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Datum Line: Point along the shoulder where the length of the camber or case is measured for headspace, varies from one cartridge to another. Specifications can be located from SAMMI or from your reamer maker.

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Deburr: To remove the small metal burrs from inside and outside the case mouth.

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Decapping: Removal of spent primers from fired cases.

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Decapping Pin: Slim needle-like rod in the resizing die, which actually pushes the spent primer out of the case.

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Decapping Rod: Normally found in the resize die, the decapping rod carries the expander ball and the decapping pin.

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Diplock’s Syndrome

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In an article by Samuel Clark Jr. originally published in "Twenty-two Caliber Varmint Rifles’’ by Charles Landis, 1945, Clark tells a story about shooting accurate rifles and the good natured jabbing and poking that will inevitably erupt among shooting buddies. Here is an excerpt:

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"The writer (Clark) had often remarked how frequently it is that we read of rifles capable of shooting into a minute of angle or how often we hear of ³A" or even Vi" groups shot from rest or a machine rest at 100 yards, or 2 or less than 2 groups at 200 yards. It has also been frequently noted that although shooting, as just described, causes no great stir among the shooting fraternity, nevertheless, such shooting even in the hands of well-known experimenters, equipped with the most accurate rifles obtainable, has not been the rule on the range described above—in fact far from it—actually, quite the contrary, and if all groups fired by each individual shooter were averaged, the result would indicate the progress along the lines of accuracy was a very dubious matter indeed.

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Among visitors to the range who had not neglected to observe this point, was Clark’s good friend and genial shooting companion, John Dip lock. In fact, Diplock had so often been disappointed when rifles which were described as tack drivers failed to shoot in the vicinity of the tack, let alone shooting group after group measuring 1" or under, that he had lost a great deal of faith in the expressed opinions of his fellow man.

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Another illusion, which Diplock had learned to discount about 99%, was that of the dependence that could be placed in the 5-shot groups as a test of accuracy. The whole matter had been discussed from all possible angles and the opinion was firmly held that a group of 10 shots fired from any rifle from bench or machine rest at 100 yards, which measured 1" from center to center of bullet holes farthest apart, was still a mighty fine group, and despite claims to the contrary, that the rifle and rifleman, who could sit down and do such shooting when the chips were down, with spectators present, and continue to do it for 10 shot group after 10 shot group, just had not come along yet.

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Diplock, sensing an opportunity to turn the weekend into a payday, pounded his fist on the loading bench and stated that he had listened to all this 1 talk he wanted to, and he had seen all the selected groups he wanted to see, but what he did want to see was a shooter who was man enough to demonstrate before witnesses and with money on the board, what he could do about this 1 business... Peeling a big bill off his roll, Diplock laid it on the loading bench and announced that he had had his say."

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Why repeat all this here? Well, for years gunsmith’s have had the reputation of being grumpy, opinionated, old duffers. It is the author’s (Zeglin) contention that the story above is a good explanation for the attitudes displayed by many long time gunsmiths. Professional gunsmiths are forced to endure amazing tales of accuracy, and hunting prowess, most of which no 5 year old would believe. After some exposure to such comments, stories, statements, anecdotes, yams, legends, and/or outright lies even the kindest heart will become hardened to these tales. This hardened condition the author has dubbed Diplock’s Syndrome. By the way, Diplock lost his bet... nobody is perfect.

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Expander: The part of the die that expands the case mouth to receive the bullet. Also called expander-ball.

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False Shoulder : When forming a wildcat from parent brass of a larger neck diameter, a new shoulder is formed in a sizing die at the correct point to properly headspace the new case in the wildcat chamber, for fire forming. Pictured below.

False Shoulder

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Finish Reamer: Chamber reamer, reams the chamber to final dimensions. Often referred to simply as a chamber reamer.

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Fire Forming: The process of fully forming cases, by firing them in a larger chamber. Headspace must be observed.

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Flash Hole: The hole in the center of the primer pocket that allow the fire from the primer to ignite the powder in the case.

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Form dies: Dies used to form brass to a new shape, such dies are common to wildcatting.

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Forming: The process of shaping brass in form dies.

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Full Length Sizer: A die used to resize the full length of the case to minimum specifications.

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Handloading: The process of loading ammunition by hand. Also known as reloading.

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Hangfire: Slang term for any detectable delay in cartridge ignition.

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Headspace: Measured distance from the bolt face to a predetermined point on the case. Rimmed cases headspace on the rim. Rimless, semirimless, and rebated cases headspace on the shoulder of the case at a point called the datum line. Belted cases headspace on the belt.

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Headspace Gage: Solid steel tool made to measure headspace for specific cartridges by inserting the gage in the chamber and checking fit.

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Ignition: The action of setting the powder charge on fire.

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Jacket: The outer skin of the bullet, normally copper alloy.

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Lands: Raised portion of the bore not cut away, creating rifling.

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Misfire: Failure of the cartridge to ignite after the firing pin has struck the primer.

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Neck: Portion of the case, which retains the bullet. In bottle neck cases that portion of the case forward of the shoulder.

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Neck Sizer die: A die used to size only the neck of the case.

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Ogive: Curve of the bullet ahead of the bearing surface.

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Powder: The propellant used in cartridges to generate energy to push the bullet down the bore.

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Powder Charge: Specified amount of powder loaded in the cartridge.

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Primer: Small cap containing a detonating mixture used to ignite the powder charge in the case.

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Primer Pocket: Cavity in the base of the case where the primer is seated.

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Priming: Process of installing new primers in cases.

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Ram: The part of the reloading press which holds