First 13 Pages Of Book Flashcards
Cycle of operations
Feeding Chambering Locking Firing Unlocking Extracting Ejecting Cocking
Feeding mechanisms
Magazines
Belts
Clips
Magazine types
Box (staggered or in line)
Drum
Pan
Types of belt
Split-link (180 degree encase) Fully encased (360 degree encased)
Disintegrating (belt Dallas apart after firing)
Non-disintegrating
Clip types
En-bloc clip
Stripper (charger) clip
5 types of cartridge cases
Rimmed (larger base, no milled extractor groove)
Semi-rimmed (larger base, has milled groove)
Rimless (same size base, has mulled groove
Belted (cartridge with rimless base, has thick band/belt just forward of milled groove)
Rebated (smaller base, has milled groove)
5 veriaties of firing pins
Free floating Inertia Percussion Striker Fixed
3 ways firing pins receive energy
Larger mass strikes pin (free floating)
Spring provides energy (inertia, perc., striker)
Their own mass provides energy (fixed)
Components of primers
Cup, explosive, protective foil, anvil in primer or in cartridge case
Two types of primer
Berdan (anvil in cartridge case, two flash holes) non-reloadable
Boxer (anvil built in primer, one flash hole)
Locking systems
Rotating bolt Rising/lowering bolt Roller Rising barrel Locking flaps Swinging bolt Locking block Rotating barrel
Operating systems
Bolt action Blowback Delayed blowback Recoil Recoil with gas assist Gas operation Manual pump Revolving cylinder
Types of gas operation operating systems
Gas blast
Gas tappet
Gas direct
3 types of recoil
Long action, short action, inertia
3 types of sights
Fixed, adjustable, back-up
Cartridge case type
Rimmed Semi rimmed Rimless Belted Rebated
Cartridge case measurement military
Diameter of projectile X length of cartridge case expressed in mm
Caliber measurement
Distance across the bore of the weapon from land to land expressed in 100th of an inch
MOA
1 degree= 16 MOA
1MOA at 100 yards =1 inch
Error at 1000 yards= .5 inches
MIL angular measurement
1 Mil=3.5 MOA
1mil at 100 m=10 cm
Shotgun shell components
Crimp Case Shot Wad powder Brass head primer
Shotgun gauges
Number of balls required to equal 1 pound
Choke
Tapered constriction of barrels bore at muzzle end, tightens the spread pattern
Types of choke
Full
Improved
Modified
Cylinder
Parts of trajectory
Rising branch
Maximum ordinate
Falling branch
Rising branch
Part of trajectory when bullet leaves barrel until just before max ordinate
Maximum ordinate
Highest point of bullet trajectory, usually about 2/3 distance to target, never higher than bore line
Falling branch
Max ord. To target
Ballistics def.
Science and study of the motion and impact of projectiles
Types of ballistics
Internal
External
Terminal
Battle sight
The range that allows you to hit the target between the throat and waist with out sight adjustments.
Breech
Outside rear face of the barrel which meets the face of the bolt or breechblock
Breechblock
A component that seals the breech and blocks gases from the fired cartridge.
Chamber
The unruffled portion of the bore at the rear end of the barrel that receives and supports the cartridge when the breech is closed.
Fluted chamber
Chamber with raised lands to improve cartridge extraction.
Compensator
A device attached to the muzzle of a weapon designed to allow the gases following a bullet out of the muzzle to be deflected upward through slots in the top surface of the compensator. Lower portion is solid, so while some gas escapes from the top, gas is also pushing down against the bottom. This downward pressure keeps the muzzle down which retards muzzle climb which is an instability factor
Disconnector
Device incorporated into the action of a weapon which prevents the firing of more than one shot for one pull of the trigger, or which prevents the weapon from being fired until the action is fully closed.
Ejector
A cam or projection inside the receiver against which the cartridge case strikes and is thrown clear of the mechanism after it has been drawn from the chamber by the extractor.
Extractor
Component that engages the the rim or extractor groove of the cartridge case while the cartridge is in the chamber. After firing the extractor withdraws the case from the chamber when the action opens.
Firing pin
The part of the firing mechanism that strikes or contacts the primer of the cartridge to cause ignition to fire the weapon
Flash suppressor
A 3 or 4 pronged device attached to the muzzle of a weapon designed to cool the hot gases as it leaves the muzzle behind the round, cooling the gases reduce the flash.
Grooves
The portion of the rifling in a barrel that in conjunction with the lands impart the spinning motion to a bullet.
Headspace
The distance from the breechblock to the part of the chamber that stops forward movement of the cartridge case.
Lands
Raised portion between the grooves in the bore of a gun that impart the spinning motion to the bullet.
Muzzle break
Device at the muzzle end of the weapon which deflects the emerging powder gases. The energy imported by this act of deflection pulls the weapon forward to offset some of the rearward motion of recoil.
Primer
Small charge that is detonated by the firing pin, which in turn ignites the powder of propelling charge on the cartridge.
Recoil
Rearward movement of weapon caused by the expansion of the powder gases which act to thrust the projectile forward on the barrel and react to move the weapon rearward.
Sear
A component retained under spring tension that releases, by means of a trigger, either a firing pin, hammer, or bolt.
Trigger
A finger actuated lever used to activate the firing mechanism firing the weapon.
Trigger bar
A connecting bar operating between the trigger and the sear. Nothing more than an extension of the trigger.
Fors
Forward opposite
Back same
