Gunsmithing student help with Cycle of Operations

Discussion in 'Gunsmithing Forum' started by MrCarson, Jul 10, 2014.

  1. MrCarson

    MrCarson New Member

    I need to do a cycle of operations for each firearm I blue during school & it would be helpful if someone could read over it for me. The firearm is a Stevens favorite model 30g. I'm a little unsure of the trigger mechanism but if you see something wrong or something that could be worded better please let me know. Thanks



    The dot is the operation and the definition. under it is my answer.

    •Firing - Firing is initiated by the operation of the trigger mechanism releasing the hammer or striker.

    There is a main spring & main plunger rest against the hammer. The trigger stays in the forward position because of the trigger spring that’s behind the trigger. The hammer has a notch on the bottom of the hammer. As the hammer is rotated back putting tension on the main spring, the notch on the underside of the hammer locks with the notch on the top of the trigger. This puts tension on the trigger spring & locks the hammer back. When the trigger is pulled it releases the tension on the main spring & plunger, which forces the hammer forward & strikes the firing pin that’s in the breech.

    •Unlocking - The process of disengaging the bolt or breech face from the closed (and physically blocked) position behind the chamber. In some firearms there are no physical lock, other than the weight of the bolt. This is known as blow-back operation.

    The lever houses a detent plunger & spring, this resist against the link that that is pined to lever. The other end of the link is pined to the breech. The extractor pivots on the pin that holds the lever to the receiver. When the lever pivots forward it pivots the breech into the receiver & pulls the extractor away from the chamber simultaneously.

    •Extracting - The process of pulling the cartridge case out of the chamber. Extraction may be divided into two phases with more leverage applied to the initial (or primary) extraction. Primary extraction must overcome the friction between the case and the chamber walls.

    When lever is pivoted forward this allows the breech & the extractor to open simultaneously. As the breech is pivoted into the receiver, the extractor pivots away the chamber & extracts the cartridge. Then the cartridge must be removed by hand.

    •Ejecting - The process of forcefully throwing or otherwise removing the cartridge case from the receiver.

    Ejecting the cartridge is done by hand.

    •Cocking - The process of retracting a hammer or striker, against spring pressure, so that the hammer or striker stores kinetic energy. This energy will be released in the firing process to strike and ignite the primer. In most cases, cocking occurs before feeding, but this is not always the case. Exceptions include bolt actions that cock on closing and many single-shot, hammer fire guns. If loading has not been done previously, it must be done at this point to continue.

    Cocking is done pulling back the hammer by hand. While cocked the lever is pivoted forward which opens the breech & extractor allowing a cartridge to be chambered by hand. When the hammer is cocked it puts tension on the main spring & main plunger that rest against the hammer, the trigger keeps the hammer cocked & keeps the tension. When the trigger is pulled this releases that tension & the hammer strikes the firing pin that’s housed in the breech. The firing pin spring keeps the firing pin in the breech until the firing pin struck.

    •Feeding - The process of moving a cartridge from the magazine to the chamber mouth. If there is no magazine, the process is completed by hand.

    This is done by placing a cartridge into the chamber one at a time.

    •Chambering - This is the process of fully seating a cartridge in the chamber.

    When the lever pivots forward it pivots the breech into the receiver & pulls the extractor away from the chamber simultaneously. Place the cartridge in the chamber with the rim of the cartridge resting against the extractor. Then by pivoting the lever back the breech & extractor pivot forward, this sits the cartridge into the chamber.

    •Locking - The process of holding the bolt or breech face in a fixed position, sealing in the cartridge, so that it will not be dislodge upon firing.
    As mentioned in the Unlocking step, blow-back firearms do not lock.
    When the lever is pivoted back it closes the breech & extractor sealing the cartridge. In the receiver there is a lip or either side to guide & secure the receiver into place.
  2. c3shooter

    c3shooter Administrator Staff Member

    Think you covered it well.