Section Two: Ammunition

Transcription

1 Section Two: Ammunition Familiarization with ammunition is a must if you are going to possess a modern firearm and use it safely. Ammunition comes in many different calibers (sizes) and two different configurations: Centerfire and Rimfire. This section will cover the different kinds of handgun ammunition and what you should know as a firearm owner. Cartridges All handgun ammunition is made up of four major components. These components are: (see Figure 1 below for Centerfire cartridges. See Figure 2 for Rimfire cartridges.) 1. Case a metal cylinder (usually brass) that holds the other 3 components. 2. Primer an impact sensitive compound used to ignite the powder. 3. Powder fast burning compound used as a propellant contained inside the case. 4. Bullet a projectile, usually made of lead, located at the mouth of the case. Bullets may be lead and are most commonly covered in copper. Look at Figures 1 and 2 closely and you will notice that the primer is different for the two different types of ammunition. Primer Bullet Powder Figure 1 Centerfire Cartridge Figure 2. Rimfire Centerfire ammunition gets its name from the primer being in the center of the bottom of the cartridge. Rimfire ammunition gets its name from the primer being inside the rim of the cartridge.

2 Cartridge Cases The cartridge case of your ammunition may be: 1. Rimmed most often used in revolvers. The cartridge rim is wider than the body. (See Figure 3) 2. Rimless most often used in semi-auto pistols. The rim is the same diameter as the case. (See Figure 4) Figure 3 Figure 4 Rimmed Rimless Now that you understand how cartridges are made, let s go into more detail on their functioning, and the firing sequence of a cartridge. In the drawings below, you can see three separate events happen when a cartridge is fired. If your firearm is operating correctly, when you pull the trigger the hammer or striker strikes the firing pin. Once that occurs the following happens: 1. The firing pin strikes the primer. Once struck, the primer compound creates a small explosion igniting the powder, much like a spark plug in a car ignites gasoline. 2. The ignited powder burns at such a fast rate that it produces an incredibly high volume of gas, in a very short period of time. The rapidly expanding gas propels the bullet out of the cartridge, down the barrel, and out the muzzle.

3 Modern gun powder comes in many different forms. The explanation of the different kinds of powder is beyond the scope of this course, but the information is readily available should you wish to find out more on the subject. There is a common misconception that gunpowder explodes. That is true of old-fashioned black powder cartridges, but not of modern gunpowder. CALIBER When discussing the caliber of a cartridge, we are referring to the approximate diameter of the bullet measured in hundredths or thousandths (decimal) of an inch or in millimeters. Figure 6 When measured in inches the caliber is generally considered an American designation. When measured in millimeters, the caliber is generally considered a European designation. Examples:.45 caliber is approximately 45 one hundredths of an inch in diameter.357 caliber is approximately 357 thousandths of an inch in diameter 9mm is approximately 9 millimeters in diameter

4 Exceptions to the diameter rule Exception One. The 38 Special cartridges and the.357 magnum cartridges are the same diameter, (for reasons to obscure to explain in detail here, the.38 special caliber is actually.357 inches in diameter.) Notice in Figure 7 below that the.357 Magnum cartridge is longer than the 38 Special cartridge. 38 Special rounds fit in and are often fired in a.357 Magnum firearms. However,.357 Magnums should not fit into a 38 and should only be fired in a.357 Magnum firearm due to the higher pressures produced by the.357 cartridges. Figure 7 IMPORTANT Always follow the firearm manufacturer s direction when choosing ammunition.

5 Exception Two. The most common of the 9mm calibers is the 9mm Luger, also called 9mm Parabellum or 9mm NATO or the 9X19 (9 by 19.) It is a 9mm diameter bullet in a 19mm long case. The 9mm Luger is the most commonly confused cartridge and it is NOT to be confused with or interchanged with other 9mm rounds of different case lengths. Examples of other common 9mm rounds: 9mm Kurz also called the 380 ACP 9mm Makarov (9mm x 18mm) 9mm Largo (9mm x 23mm) Figure 8 Now that you have a basic understanding of ammunition, let s discuss how to ensure you get the proper ammunition for your firearm. Choosing The Proper Cartridge

6 It is essential that only the proper cartridge be fired in the gun being used. Make sure to check the markings on the gun with the cartridge designation prior to use. (See Figure 9) Using the wrong cartridge in your gun can cause devastating injuries or even death. It is of the utmost importance that you only fire the ammunition in your firearm that is recommended by the manufacturer. An easy way to find out of you have the correct ammunition for your firearm is to use the BARREL - BOX - BOTTOM of cartridge case rule. Figure 9 Modern firearms should have the recommended caliber for that firearm stamped on the barrel. (Notice the stamped caliber on the two barrels above.) If the caliber is not stamped on the barrel, do not fire the gun. Take the firearm to a qualified gunsmith to find the correct caliber of ammunition.

7 Once you know the correct caliber you can then purchase ammunition for the gun. When purchasing ammunition check to make sure the ammunition box matches the caliber stamped on the barrel. Once you are sure the box and barrel match, check the bottom of the bullet to ensure it is stamped with the correct caliber. (It seldom happens, but it is possible that the wrong size ammunition was placed into the wrong box.) Do not use +P or +P+ ammunition in a gun not designated for use with that type of ammunition ( +P indicates ammunition loaded to higher than standard pressures). You need to check your owner s manual or contact the manufacture to see if you gun can shoot +P or +P+ cartridges. If you do not have an owner s manual, look up the manufacture up on the Internet and sometimes you can down load owner s manuals. Common ammunition manufacturers and their web addresses. Winchester - Remington - ATK makers of American Eagle, CCI, Blazer and Speer - PMC - Hornady - Magtech - This is just a sampling of manufacturers. You can find many more with an online search. A word of warning about reloaded ammunition - be extra diligent in checking to make sure the ammunition is right for your firearm. Reloaded ammunition can sometimes be labeled wrong or loaded incorrectly with too much powder or not enough powder. Too much or to little powder are both dangerous.

8 Cartridge Malfunctions Like anything mechanical, cartridges can malfunction. The three most common are: 1. Misfire a misfire is a failure of a cartridge to fire after primer is struck by the firing pin. If you pull the trigger of your gun and nothing happens, you probably have a misfire. If this happens, wait 30 seconds before you do anything. Just in case you may have a hangfire. (See 2 below.) Once you are certain you do not have a hangfire, you can remove the misfired cartridge and replace it with a new cartridge. (The cartridge to the right is a good example of a misfired cartridge. Notice the dented primer.) 2. Hangfire a hangfire is a perceptible delay in the ignition of the cartridge after the primer has been struck by the firing pin. The trigger is pulled and nothing happens. Then, after a few seconds, the gun fires. Hangfires are very rare in modern ammunition but they are extremely dangerous. Hangfires occur most often in black powder cartridges, or older cartridges that have not been stored correctly. If you suspect a hangfire you MUST keep the firearm pointed in a safe direction until it fires, or until you are certain it is not a hangfire. 3. Squib Load a squib load happens when less than normal pressure builds up in the cartridge after the ignition of the primer. This pressure is not enough to force the bullet out of the barrel resulting in the bullet getting stuck in the barrel. A good rule for squib loads is if you hear pop stop. If you have a shot that sounds, and or feels funny, stop and safely check the barrel. If you shoot another cartridge with a bullet lodged in the barrel of the firearm it could cause serious harm or death. At a minimum it will probably ruin the barrel of the gun. (See Figure 10) Semi Auto Pistol Barrel Revolver Barrel Figure 10 Never look down the barrel of a loaded firearm to check for a squib load. Use a wooden rod or some other tool to see if a bullet is blocking the barrel. If there is a bullet lodged in the barrel see a professional armorer or gunsmith to have the bullet removed. Clearing Cartridge Malfunctions

9 1. Always keep the gun pointed in a safe direction. 2. Do not attempt to open the action for at least 30 seconds to be certain you do not have a hangfire. 3. Use the clearing procedures taught by your in-person instructor, or use the procedures shown in sections four and five of this course IMPORTANT: Never remove a gun from the firing point that has a cartridge malfunction. If you are unable to clear the firearm, leave it at the firing point, pointed downrange and get assistance from range personnel. G. Ammunition Storage Figure 11 There are three main destructive forces when it comes to ammo storage:

10 1. Heat can break down both the components in cartridges. This can lead to ignition problems and possible squib loads. Cold should not affect ammunition. However, you should not expose your ammo to heat and cold as this can cause condensation inside the cartridge. 2. Moisture can lead to corrosion of the cartridge case. Corroded cases can be dangerous if the case thickness is reduced. It is also possible the corroded cases can get stuck in the chamber causing a failure to extract the case from the chamber. 3. Chemicals, solvents, cleaners, and oils can penetrate cartridges damaging improperly sealed ammo. This can also lead to defective ignition or squib loads. Short-term storage The boxes that ammunition is sold in are fine for short-term storage, provided your ammo is kept away from heat, moisture and chemicals. Long-term storage Any paper-based ammunition storage is not ideal for anything longer than a year or two. For long-term ammo storage and to ensure your ammunition retains optimal characteristics, commercial or military ammunition boxes are the best options for storage. These boxes can be purchased in both metal and plastic configurations. Be sure to label the outside of your container with cartridge, caliber, and the date. This will help you when you rotate your stock, using up the older ammunition before using the newer stock. Periodically check your ammo for moisture or corrosion. U.S. Military Metal Ammo Can Commercial Plastic Ammo Can

11 Sporting Arms and Ammunition Manufacturing Institute Information on Ammo The following information is provided courtesy of SAAMI the Sporting Arms and Ammunition Manufacturers Institute. SAAMI was founded in 1926 at the request of the federal government to set standards for ammunition and firearms quality. This leaflet has been prepared by the Sporting Arms and Ammunition Manufacturers Institute, based upon information currently available to it. It is furnished to interested persons as a courtesy and in the interests of safety. It is not intended to be comprehensive; it does not modify or replace safety suggestions, standards, or regulations made by designated authorities, public or private. It is subject to revisions as additional knowledge and experience are gained. SAAMI expressly disclaims any warranty, obligation, or liability whatsoever in connection with the information contained herein or its use. These paragraphs are meant to give everyone concerned for the shipment, storage and handling of small arms ammunition certain basic and important facts about the properties of this widely distributed product. Such information should dispel some of the rumors and tales which persist regarding ammunition bulk safety. It also outlines recommended storage conditions, and reports the reactions of ammunition when exposed to fire or intense heat and rough or vigorous handling. These statements and recommendations do not supersede local, state or federal regulations. Local authorities should be consulted regarding regulations on the storage, transportation, sale and handling of sporting ammunition in each specific community. Properties of Small Arms Ammunition All ammunition is carefully engineered and manufactured as an article of commerce. It has a specific use; if stored in a proper manner and used as intended in firearms in good condition and designed for the specific cartridge, the safety and satisfaction of the shooter should be assured. Small arms ammunition is packed in cartons and cases as specified by the US Department of Transportation. These container designs were developed in the interest of safety in transportation, storage and marketing. Therefore, unapproved packaging should never be substituted. Specific properties or characteristics of small arms ammunition of particular interest to shippers, warehouse operators, dealers and users are as follows: Stocks of small arms ammunition will NOT mass explode. That is to say, if one cartridge or shotshell in a carton or case is caused to fire, it will not cause other adjacent cartridges or shotshells or their packages to explode sympathetically or in a simultaneous manner. There are no limits imposed on packaged quantities of ammunition which may be shipped, warehoused or displayed in commercial establishments. This fact recognizes the inherently safe, non-hazardous characteristics of such ammunition in public or private storage. Small arms ammunition is not a super-sensitive item. Packages of ammunition may be dropped from any height which the packages will physically withstand, and cartridges or shotshells therein will not fire due to the shock. Properly packaged small arms ammunition will withstand all the rough handling tests of commerce such as drop test, vibration tests, and rotating drum tests without individual cartridges or shotshells firing. Small arms ammunition, if discharged in the open without the support provided by a firearm s chamber or other close confinement, discharges inefficiently. The flights more accurately movement of projectiles or debris particles from such incidents are extremely limited in velocity, range and energy. The small primer cups or rimfire case fragments are the missiles of highest velocity in such occurrences. Specifically, bullets and shot charges, being heavier than shell or cartridge cases in most instances, are rarely projected away from the location at which the unchambered round of ammunition was caused to ignite and discharge. However, small particles of metal or

12 plastic from the burst case and primer cups may be propelled for short distances (usually not over 50 feet) at velocities sufficient in some instances to cause injury or discomfort. Insofar as the Sporting Arms and Ammunition Manufacturers Institute has been able to determine, there have been no substantiated reports of serious or fatal injuries caused by the discharge of packaged or loose ammunition in handling or in fires, regardless of the quantity or type of cartridges or shotshells involved. SAAMI has no verified report of any fire fighter hurt by flying bullets or shot pellets in fires involving a sportsman s in-the-home personal supply of ammunition, a retail sporting goods store s stock, wholesaler s or distributor s sizable inventory, or an intransit cargo of this product. Handling and Storage of Ammunition Small arms ammunition contains explosive ingredients: A percussion-sensitive primer mixture and a smokeless propellant. It should be treated with respect and care in all handling, transportation and storage. Ammunition should be stored in the factory carton or package. The labeling and identification on the original container help to assure that future use will be in the gun for which the ammunition is intended. Ammunition stored in the home, retail outlet or distributor s warehouse over extended periods in factory packaging, subject to the ordinary variations of temperature and humidity ranging from tropic to Arctic conditions, can be expected to perform satisfactorily and safely in the firearms for which it was intended if such firearms are in proper working order and condition. Extreme high temperatures (over 150 F) however, should be avoided. Ammunition should not be immersed in water or exposed to any organic solvent, paint thinner, petroleum product, ammonia, etc. Such materials may penetrate a loaded round and reach the powder or primer; a deteriorating effect will result which may cause misfires or squib shots. The latter can result in a projectile s lodging in a gun barrel, the obstruction possibly causing serious damage or injury when another shot is fired. Ideally, home storage of small arms ammunition is in a locked closet or cabinet out of the reach of children and uninformed or incompetent persons. Both guns and ammunition should be stored out of sight and reach of children and others not physically or mentally capable of giving them correct, proper use and respect. Storing guns and ammunition in locked auto trunks may be convenient, or required by state or local law, during short periods when moving to and from the hunting field or target range. The possibilities of extremely high temperatures make it sensible to remove firearms and ammunition from vehicles following the trip. The passenger compartment of a closed car when exposed to the sun often develops an extreme high temperature and is thus not a desirable spot to leave ammunition. While blank cartridges will not mass detonate if one in a box is caused to fire, the noise of firing outside a gun will be nearly as loud as in normal use and may be harmful to hearing. The blank s explosion may also be rather violent due to rapidly expanding gasses released during burning. Obviously, blank cartridges deserve the same respectful handling and careful storage as other ammunition. Retail and wholesale stocks of ammunition, not required for display, should be stored in original outer cartons or boxes exactly as supplied by the factory. When placed on basement or warehouse floors subject to moisture it would be well to stack the cartons on pallets. In some locations police or public security regulations may prescribe the manner in which small arms ammunition stocks are displayed and the quantity that may be in sight. Check with local authorities. Packages of ammunition should not be placed in proximity to heavily trafficked aisles in the reach of children. Small Arms Ammunition in a Fire Although much has been written and rumored about the 4thof-July characteristics and so-called havoc of ammunition in fires, it just isn t so. Members of firefighting units are understandably uneasy when confronted by fires where ammunition is involved. Several members of the Sporting Arms and Ammunition Manufacturers Institute have undertaken extensive experiments to show what can be expected when ammunition is involved in a fire. These companies have also made careful investigations after such fires, which show that the missiles do not have sufficient energy to penetrate the garments and protective gear worn by fire fighters.

13 Tests also show that the whizzing sound heard in the vicinity of ammunition fires are caused by primers expelled from the burning cartridges. The pops and bangs are exploding primers; the propellant powders burn inefficiently and make little noise. Metallic cartridges in a fire are difficult to sustain in a burning condition once the packing materials have been consumed due to the cooling effects of the metal parts and the relatively high ratio of metal weight to smokeless powder. Only a vigorous fire around metallic ammunition stocks will cause all cartridges to burn. Shotshell ammunition is difficult to ignite, but once ignited it will sustain its own burning due to the plastic or paper tubes (hulls). Disposal of Unserviceable Ammunition Ammunition that has been in a structural fire, and has become wetted or scorched, or has been exposed to flood waters should never be returned to commercial sales channels or sold at salvage sales, since it could be rendered dangerous to the shooter by such exposure. It should be scrapped. Never dispose of ammunition by burying it or dumping it in a waterway. It may be retrieved years later, fully live, and pose dangers to children or uninformed persons. Under most circumstances, unserviceable ammunition may be scrapped by returning it to the manufacturer. Written permission should first be obtained from the Product Services Manager of the manufacturer before shipment is made. Note from ElectronicCCW. Many shooting ranges have the ability to recycle faulty ammunition. You may wish to call them before shipping to the manufacturer Please continue to the next section.