Block 6 Revolvers and Pistols

Define parts that perform the same function in Colt, Smith & Wesson, & Ruger revolvers

Colt: Ratchet, Latch, Strut, Bolt, Hand, Safety Lever

S&W: Extractor, Thumbpiece, Sear, Cylinder stop, Hand, Hammer Block

Ruger: Ejector, Cylinder release button, Dog, Cylinder latch, Pawl, Transfer bar

Revolver

a firearm with a cylinder having several chambers so arranged as to rotate around an axis.

Forcing Cone

the tapered entrance to the bore at the breech end of a revolver barrel

Rebound slide

- a reciprocating device found in some double action revolvers which moves the hammer into a position in which there is no contact of either hammer and firing pin or firing pin and primer. it can also be used to position a safety device between the hammer and firing pin or primer

- a spring-loaded metal block which directly impinges on the trigger in S&W revolvers. the rebound slide causes the trigger to return to its forward position and rebounds the hammer. the primary safety & prevents firing if dropped.

Hammer block

a physical block, that when the hammer is in the resting position, the upper end of the hammer block lays between the face of the hammer and the frame. Pulling the trigger will lower the hammer block that then allows the hammer to strike the primer.

You need to visually inspect and ensure the hammer block is moving down as the trigger is pulled.

Transfer bar

At rest: without the trigger pulled, the transfer bar sits too low to connect the hammer to the firing pin. If the hammer falls, it strikes the frame, not the firing pin.

When fired: when the trigger is pulled, the transfer bar is raised into a vertical position between the hammer and firing pin.

Transfer mechanism: the hammer hits the transfer bar, which then hits the firing pin, firing the cartridge.

You need to visually inspect and ensure that the transfer bar is moving up when the trigger is pulled.

Single action to a revolver

the hammer must be cocked to manually rotate the cylinder and pulling the trigger releases the hammer causing discharge.

Double action to a revolver

pulling the trigger causes rotation of the cylinder, cocking of the hammer and firing of the revolver.

Describe the Lab procedure for measuring trigger pull on a single action revolver on trigger scan

After numbering the chambers, take three measurements from chamber 1 and report on worksheet.

1 is the most recently fired and note that the first chamber was used

Describe the Lab procedure for measuring trigger pull on a double action revolver on trigger scan

After numbering the chambers, take three measurements from each chamber and report on worksheet.

How can trigger pull be lightened in a revolver?

Single action: alter the rebound slide (cutting the main spring or changing it out for a lighter one), Polish the trigger sear,

Double action: alter the main spring (change it out), loosen the strain screw on a leaf type main spring, Polish the trigger nose/DA sear.

What does the direction of the cylinder stop indicate?

the rotation of the cylinder

Define cylinder flare / smoke ring

Cylinder flare: the deposit of GSR around the front margin of the chamber that is deposited during the firing process. also known as smoke ring or halo.

The halo gives indication as to which cylinder was last used due to the halo being darker.

What is the difference between the old and new Ruger Blackhawk?

the new model has a transfer bar

Short recoil-operated

a locked breech autoloading mechanism where the barrel and bolt are locked together by locking lugs for a short period during firing and then unlock by the barrel tilting so the bolt can continue rearward and eject the spent cartridge.

What is striker fired? advantages and disadvantages

A striker mechanism can be partially or full cocked by the slides movement and when the trigger is pulled will release the striker to hit the primer.

advantages: Simplicity, consistent trigger pull, lightweight and slimmer profile

disadvantages: Lack of second strike capability (except Taurus), feel of the trigger being less crisp

What is hammer fired? advantages and disadvantages

A hammer strikes the firing pin to ignite the cartridge. the hammer can be internal or external as well as SA or DA.

advantages: control over firing mechanism, more crisp trigger pull

disadvantages: More complex, and bulkier design

What is the difference in the Jennings Nine and 48?

The Nine has a fixed ejector at 6 o'clock instead of a firing pin ejector and the presence of a magazine disconnect.

Cobra FS380

lower end striker pistol, if the grip panel is not screwed in tight enough it can affect the trigger bar and cam interaction leading to improper functioning.

H&K UPS Compact

Polygonal rifling has low potential for subclass with the exception of poly with rails that has high potential in the rail.

IMI Baby Desert Eagle

quarter cock

Springfield XD-9 Sub-Compact

loaded chamber and striker status indicators

Balloting

rifling skips. Bullet ballot when it moves through the bore of the firearm with a bumping, buffeting action resulting in incomplete intermittent rifling impressions often extending to the ogive of the bullet.

Ring of Fire firearms

Raven Arms, Jennings Firearms, Davis Industries, Bryco Arms, Sundance Industries, Lorcin, Phoenix Arms, Cobra, Jimenez

Pistol

handgun in which the chamber is integral with the barrel

Semi-automatic

firing one round with each pull of the trigger

Fully-automatic

firing continuously as long as the trigger is held down until ammo runs out or a malfunction occurs.

Ejection port

An opening in the receiver or slide to allow for ejection of a cartridge, cartridge case, or shotshell.

Feed Ramp

A sloped surface located at the mouth of the chamber that serves to guide the cartridge as it is fed from the magazine into the chamber. Also known as cartridge ramp or feed throat cartridge guide.

Magazine

A container for cartridges which has a spring and follower to feed those cartridges into the chamber of a firearm. The magazine may be detachable or an integral part of the firearm.

Passive safety

A safety or safety mechanism that is inherent in the design of the firearm and is engaged until operation of the firearm disengages the safety.

Slide

A component, typically found in semiautomatic pistols, that moves in line with the axis of the bore during the cycle of fire. The slide generally houses the firing pin/striker and the extractor, and serves as the breech bolt.

Trigger guard

A rigid loop which partially surrounds the trigger to prevent damage or an accidental discharge.

Trigger Pull

amount of force in pounds which must be applied to the trigger of the firearm to cause it to discharge.

Manual safety

any external user operated levers or button that require deliberate physical action from the shooter with some needing to be disengaged before firing.

Grip safety

An auxiliary locking device on the grip of some handguns which prevents firing until it is depressed by grasping the grip correctly.

Loaded chamber indicator

A mechanism on a firearm that reveals when a cartridge is chambered if the firearm is in battery. May take the form of a small rod, raised extractor, or other mechanism that protrudes or raises to indicated a loaded status. A small opening in the chamber can also function as a chamber indicator

Firing pin block

A plunger style safety within a firearm slide that blocks the passage of the firing pin/striker through the firing pin channel through interaction with the trigger bar

Cycle of fire

Feeding: new round comes from magazine by the slide

Chambering: cartridge seated into barrel

Locking: barrel and slide lock together

Firing: trigger is pulled and releases hammer or striker

Obturation: expanding gases seal the case against chamber walls

Unlocking: barrel and slide unlock as barrel moves backwards

Extracting: extractor pulls fired cartridge from the chamber

Ejecting: cartridge case is thrown out of pistol by ejector

Cocking: rearward motion of slide resets the trigger mechanism and cocks the hammer or striker

cycle continues until mag is empty or a malfunction occurs.

Describe what observations you would expect to see on a cartridge case that has been fired in a firearm it was not chambered for.

shift of the firing pin impression towards the extractor or potentially pierced primers

an asymmetrical bulge on the cartridge cases side that will always face the pistols extractor

What is the main difference between the Colt 1911 Series 80 model and the Colt 1911 Series 70 model?

Series 80 has a firing pin block

Common Rifling Characteristics

9mm:

Hi-point- 3L, 9L

Ruger- 6R

Glock- 6R Poly

SCCY- 7R

S&W- 5R

45 Auto:

Glock- 8R Poly

Colt- 6L

Springfield Armory- 6R

40 S&W:

Taurus- 6R

Hi-point- 7L

380 Auto:

Lorcin- 6R

25 Auto:

Raven- 6L

Common malfunctions that can occur when using a pistol

Failure to extract, stovepipe, squibload, jam, misfire, hangfire, failure to feed

What is a function test?

in the condition received, a dry run examination of the firearms mechanical operations performed (without live ammo) in order to verify the safeties and cycling mechanisms function without issues or assist in identifying potential issues.