Basic Ops Flashcards
What are the three Feeding Mechanisms?
Magazine
Belts
Clips
What is a Magazine?
A metal or plastic box that feed by spring tension
What are the two types of Box Magazines?
Staggered Box
Inline Box
Explain a Staggered Box Magazine.
Rounds that are Staggered side-by-side in a Magazine
Explain an Inline Magazine
Rounds that are one on top of the other in the Magazine
Explain a Drum
Circular in shape, usually has multiple rows of cartridges. Attaches to the top or bottom of the weapon
Explain a Pan
Cartridges are stored perpendicular to the axis of rotation, rather than parallel. Usually mounted to the top of firearm
Explain a Belt
Used in machine guns because of their tactical role and high rate of fire.
Split Link Belt
Does not fully encase the cartridge
Fully Encased Metallic Link Belt
Completely surrounds a cartridge
Non-Disingrating Metallic Link Belt
Belts that do not come apart as each round is withdrawn
Disintegrating Metallic Link Belt
Comes apart as each round is withdrawn
Explain a Clip
A device used to rapidly load a magazine or weapon
What are the two types clips
En-Bloc Clip
Striper Clip
What are the five types of Cartridges
Rimmed Semi-Rimmed Rimless Belted Rebated
What is a Rimmed Cartridge
A Cartridge which has a head larger in diameter than the body, forming a rim or flange.
What is a Semi-RImmed Cartridge
A cartridge that has a head only slightly larger in diameter than the body, with a shallow groove machined around the circumference of the body forward of the head to provide an extractor gripping surface.
What is a Rimless Cartridge
A cartridge that has a head the same diameter as the body. With a groove machined around the circumference of the body forward of the head to provide an extractor gripping surface.
What is a Belted Cartridge
A Cartridge of the rimless type which has a think band or belt around the body just forward of the extractor groove to provide greater strength of that portion of the case.
What is a Rebated Cartridge
A Cartridge that has a base smaller than the case
What are the five types of Firing Pins
Free-Floating Inertia Percussion Striker Fixed
Explain a Free-Floating Firing Pin
Larger mass strikes the Firing Pin. Longer than its carrier; no spring is used on either forward or rearward movement of the firing pin. (M1 Garand & Carbine, M14, M16, M4, AK Rifle, RPK, SVD)
Explain an Inertia Firing Pin
Forward energy is created when the hammer strikes the firing pin. As the pin is driven forward by the strike of the hammer, the spring is compressed, creating the energy needed to reset the firing pin. (M1911A1, USP, BHP)
Explain a Percussion Firing Pin
The firing pin is driven forward by the Force of a compressed spring and is Retracted by the cam action that cocks the Weapon (M60, M2HB).
Explain a Striker Firing Pin
A firing pin which is carried inside the bolt and receives its forward momentum from its own spring, when activated by the trigger (squeezed) not struck by the hammer (P7). A squeeze-cocking system is what compresses the firing pin spring.
Explain a Fixed Firing Pin
It’s own mass provides the energy. A protrusion machined into the face of the bolt/breech which punctures the primer
when the bolt has fully chambered the cartridge. Found in most blowback operated submachine guns (Uzi).
There are only three ways Firing Pins receive their energy
- A larger mass strikes them (Free Floating)
- A spring provides their energy ( Inertia, Percussion & Striker)
- Their own mass provides the energy (Fixed)
What are the two types of Primers
Boxer
Berdan
Explain the Boxer Primer
The Boxer has a cup shaped igniting system having the anvil and flash powder built in with one flash hole in the cartridge case.
Explain the Berdan Primer
The Berdan contains only the flash powder, the anvil is part of the cartridge case and has two flash holes. Non-reloadable.
What are the eight Locking Systems
Rotating Bolt Rotating Barrel Rising/Lowering Bolt Rising Barrel Roller Locking Block Locking Flaps Swinging Bolt
What is a Rotating Bolt
The Bolt Rotates left or right to lock behind the breech
What is a Rising/Lowering Bolt
The rear of the bolt rises or lowers into a locking recess of the receiver.
What is a Roller
Rollers push out of the left and right sides of the bolt to lock into the breech
What is a Rising Barrel
The bare rises up into the slide to lock the barrel and slide together. (Also known as “Tilting Barrel” or
“Browning”)
What are Locking Flaps
Loose plates located on the bolt swing out looking into recesses in the receiver
What is a Swinging Bolt
The rear of the bolt swings out of line with the bore into a locking recess inside the receiver.
What is a Locking Block
A cam that pivots up into a locking recess
What are the Eight Operating Systems
Bolt Action Blowback Delayed Blowback Recoil Recoil with Gas Assist Gas Operation Manual Pump Revolving Cylinder
Explain Bolt Action
The operator manually retracts the bolt to eject the spent cartridge and to chamber a new round by pushing the bolt forward
Explain Blowback
Blowback operated weapons have no locking system. Exploding rounds blowback the cartridge case, forcing the bolt to the rear and cartridge out of the weapon. A new round is chambered as the bolt moves forward.
Explain Delayed Blowback
These weapons have locking systems. There is a delay long enough for the round and excess gases to leave the muzzle before the bolt is fully unlocked.
Explain Recoil
Recoil works by pressure from the fired round. The Breach is locked so that when the round is fired, the barrel moves to the rear with the breechblock or bolt in place. The breechblock remains to the rear while the barrel is forced forward by the spring. After the barrel is fully forward the breechblock is released, moving forward to chamber another round.
What are the three types of Recoil Systems
Long
Short
Inertia
Explain Long Action Recoil
The barrel and bolt recoil all the way back as a complete unit. Once the rearward movement is absorbed by its recoil spring, it unlocks from the bolt and returns to battery. After the bolt compresses the spring, it is held in the rearmost
position until the barrel returns to battery.
Long recoil systems have a distinct “Double
Recoil” feel to them.
Used primarily in Browning’s Auto-5 shotgun
design.
Short Action Recoil
Short recoil operation differs from long recoil operation in that the barrel and bolt recoil only a short distance before unlocking and “separating.” The barrel stops quickly and the bolt continues rearward, compressing the recoil spring and completing the other cycles of operation.
During the last portion of its forward travel, the bolt locks into the barrel and pushes the barrel into battery.
Used in most modern day pistols designs (M9,
BHP, M1911A1) as well as the M2HB.
Inertia Action Recoil
The Inertia Action recoil system is the reversal of the other designs (Long, Short). The Inertia system uses nearly the entire firearm as the recoiling component with only the bolt remaining stationary during firing.
Once fired, the recoil spring returns to its uncompressed state and pushes the bolt body backwards with sufficient force to cycle the action. The bolt body unlocks, then retracts the bolt head and spent round; ejecting the cartridge, cocking the hammer, and continuing the cycle of operation.
Because of this, the operating system is used only in firearms with a heavy recoil (Shotguns;
Benelli Super 90)
Recoil with Gas Assist
Operates with a recoil booster attached to the muzzle end of the weapon to trap gas, which aids in moving the barrel to the rear.
Internal piston taps on the Barrel to assist in Unlocking the Bolt; increasing the rate of fire and reliability.
Gas Operation
Gas pressure within the barrel is tapped by a gas port inside the barrel, using the energy to force the operating parts to the rear.
What are the three types of Gas Systems?
Gas Blast
Gas Tappet
Gas Assist
Gas Blast
Gas goes down the gas port into the gas cylinder and makes contact with the gas piston directly attached to the operating rod or slide.
Gas Tappet
Gas goes down the gas cylinder and makes contact with the gas piston which makes contact with the operating rod or slide.
The gas piston and operating rod or slide are separate components.
Gas Direct
Gas goes out of the gas port into the gas tube and is carried directly to the bolt or bolt carrier.
Manual Pump
Operator is required to pull the slide to the rear, extracting the fired round, and to push the slide forward chambering a new one.
Revolving Cylinder
Each round is fired when the trigger is pulled. The cylinder rotates aligning on the next chamber with the barrel so that the next round can be fired.
