As defined in Paragraph (b), Section 3, Article I of Republic Act No. 10591, or the Comprehensive Firearms and Ammunition Regulation Act, an ammunition is "a complete unfixed unit consisting of a bullet, gunpowder, cartridge case and primer or loaded shell for use in any firearm."
In the dictionary, you will find that ammunitions are defined as "the projectiles with their fuses, propelling charges, or primers fired from guns."
The term evolved around the turn of the 16th century. The term "cartridge" is derived from the words "charta" (Latin, paper) and "cartouche" (French, roll of paper) which indicates that the term originally described something other than the cartridges with which we are familiar today.
As we can guess from the source words, cartridges were initially made by wrapping powder in paper. In a later edition of Webster's Dictionary, a cartridge came to be defined as a "case capsule, shell or bag of metal, pasteboard, of the like, containing the explosive charge and in small arms and some cannon, the projectile to be fired."
This method of preparing the powder increased loading speeds, saved the powder from spillage, provided a uniform charge, and helped decrease accidental ignition.
Cartridges and ammunitions continued to evolved from then until the form that we now see today.
In general, the basic parts of an ammunition are the case, primer, powder, and projectile. Depending on the type of ammunition, additional components may be found. For example, shotgun shells have a wad.
Basic Parts of an Ammunition
case: the container that holds everything together
gunpowder: a chemical mixture whose purpose is to propel projectiles through the expanding gases produced during the chemical reaction triggered upon ignition
primer: a chemical mixture that ignites the gunpowder
projectile: the object/s expelled from the barrel of the firearm
wad: an extra container, usually made of paper or plastic, that separates the gunpowder from the slug or shots
dummy
used as a model
drill
does not contain gunpowder
blank
does not contain bullets
Pinfire
The ignition cap (primer) is concealed inside the cartridge case and has a pin resting upon it
Rimfire
The priming mixture is located at the hollow rim of the case; Can be fired if the cartridge is struck by the firing pin on the rim of the case (cavity rim)
Centerfire
The primer cup (ignition cup) is centrally placed in the base of the cartridge case and the priming mixture is exploded by the impact of the firing pin and with the support of the anvil
rimmed It has a flange at the base which is larger than the diameter of the body of the cartridge case. This flange is to enable the cartridge to be extracted from the weapon in which it is used.
rimless The flange diameter is the same as the body and there is, for extraction purposes, a groove around the case body just in front of the flange.
semirimmed It has a flange which is slightly larger than the diameter of the cartridge case and a groove around the case body just in front of the flange.
belted It has a pronounced raised belt encircling the base of the cartridge, the belt is for additional strength in high pressure cartridge.
rebated It has an extractor flange which is less than the diameter of the cartridge case.
Cal. .22 about 5.59 mm used in revolver, pistol and rifles
Cal. .25 about 6.35 mm used in pistols and rifles.
Cal. .30 about 7.63 mm (mauser) for carbines and other rifles
Cal. .30 about 7.63 mm (luger)
Cal. .32 about 7.65 mm for automatic pistols and revolvers
Cal. .357 used in magnum .357 revolvers
Cal. .380 about 9 mm used for pistols
Cal. .45 about 11 mm used in automatic pistols
Cal. .50 used in .50 cal. machine gun
A shotgun cartridge is a complete unit of unfired cartridge consisting of the pellets, primer, case, wads and gunpowder.
The unit of measurement of shotgun cartridges is expressed in gauge. This measure is based upon the number of solid lead balls contained. This number is limited by the size of the individual balls. Below is a summary table of shotgun gauges and the equivalent diameter in inches.
At present, the 10-gauge shotgun is the biggest one available while the 410 is the smallest. As noted in the table, the 410 is a caliber and not a true gauge measure.
Soft or Drop Shot made of pure or nearly pure lead to which a small amount of arsenic has been added to make it take on the form of a spherical drop as it falls down the shot tower; easy to deform or flatten; loses its velocity quicker; low penetrating power and string out more
Chilled or Hard Shot made with lead containing a small amount of antimony to increase its hardness; does not deform easily; has better patterns, less string and more uniform velocity and penetration
Coated or Plated Shot also called a lubaloy shot; a chilled shot coated with thin copper through electroplating design for greater strength and elasticity; great resistance to deformation and leading and better pattern
Buck Shot large lead shot