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MY'STORY

The MOVE Fire

This is a personal recollection on the Move fire on May 13, 1985 Philadelphia police fired thousands of rounds at the MOVE house, city officials approved dropping an explosive device on the roof, the resulting fire was allowed to burn, 11 people—including five children—died, and 61 homes were destroyed. Philadelphia City Council later called it a “brutal attack carried out by the City of Philadelphia on its own citizens” and acknowledged that no individual faced criminal consequences for the bombing. One timeline correction worth preserving for the BHP record: the major previous MOVE-police confrontation was August 8, 1978, about seven years before the bombing, not a year or two earlier. Officer James Ramp was killed, other police and firefighters were wounded, nine MOVE members were later convicted, and television cameras recorded police beating Delbert Africa during his arrest. The 1985 MOVE Commission later specifically criticized city planners for failing to adequately use lessons from that 1978 confrontation. And that actually strengthens the point you’re making: 1985 did not happen without precedent or institutional memory. There had already been a deadly confrontation with MOVE, years of conflict, negotiations and police involvement before Osage Avenue.

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BLACK FACTS
The Truths They Never Taught You...

The Violence That Helped Spark the NAACP

In August 1908, a white mob attacked Springfield, Illinois’s Black community, destroying homes and businesses and lynching two Black men. National outrage over the violence helped spur the movement that created the NAACP the following year.

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Wikipedia

Slamfire

Slamfire occurs when the cartridge discharges as soon as it reaches the chamber, rather than waiting in the chamber to receive a firing pin impact when the trigger is pulled.
Schematic of an Advanced Primer Ignition blowback operation that works in a similar way to slamfire by striking the cartridge as it is moving forward before it is fully chambered.

A slamfire is a discharge of a firearm occurring as soon as a cartridge is being loaded into the chamber. Some firearms are designed to slamfire, but the term also describes a malfunction of self-loading firearms. Shooters accustomed to firearms requiring trigger activation for discharge may be unprepared for a slamfire discharge.

Some military firearms are designed to fire from an open bolt condition to avoid the unintended discharge of a chambered cartridge cooking off in a gun barrel heated by firing previous cartridges. Activating the trigger of such firearms releases the spring-loaded bolt to move forward stripping a cartridge from the magazine into the chamber. The firing pin impacts the primer as the cartridge is chambered, and the energy released by the discharging cartridge returns the bolt into an open position while ejecting the empty case.[1]

Unintentional slamfire

[edit]

More conventional self-loading firearms begin this cycle with a cartridge already in the chamber and await activation of the trigger to allow the firing pin to impact the primer, causing discharge and loading another cartridge into the chamber. The first cartridge must be loaded from the magazine by manually pulling back and then releasing the spring-loaded bolt to chamber the cartridge; and unintentional slamfires may occur if the firing pin activates the primer as the first cartridge is being chambered. Unintentional slamfires may also occur during the normal self-loading process following an intended discharge.

Control of firing pin movement is the essential difference between cartridge discharge as the bolt closes, or discharge when the trigger is pulled. Firearms designed to discharge as the bolt closes may have a fixed firing pin or a firing pin which moves forward by inertia as forward motion of the bolt ceases when the cartridge is fully chambered, while more conventional firearms are designed to prevent the firing pin from impacting the primer until the trigger is pulled. Some unintentional slamfires are caused by firing pin malfunction, while others may be attributed to defective cartridges with improperly positioned or unexpectedly sensitive primers.

Possible causes

[edit]
The free-floating firing pin of AR-15 style rifles typically causes an indentation as the firing pin lightly strikes the primer when the bolt closes as it chambers a loaded cartridge. Although a single light indentation may not detonate the primer,[2] the indentation may make the primer more sensitive to subsequent impact. Some shooters avoid using cartridges with primer indentations from being previously loaded but not fired.

Firing pins intended to be activated by a trigger are either spring-loaded or free-floating. Both may move forward during the loading process when the face of the bolt hits the head of the chamber. Although the amount of forward movement is not intended to detonate the primer, slamfires occur when conditions do not match design assumptions.

Cartridges which may be entirely satisfactory in manually loaded firearms may be considered defective if they do not meet the design specifications of self-loading firearms. Primer depth is very important in centerfire ammunition. Most cartridges are assembled with the exposed surface of the primer a specified distance deeper than the base of the cartridge in contact with the bolt face. Primers with insufficient depth may be detonated by the normal amount of firing pin movement as the cartridge is chambered by forward bolt movement. Primer response to impact is a function of the thickness and hardness of the metal cup containing the detonating explosive. Primers intended to respond to the comparatively light firing pin impact of older or smaller manually-loaded firearms may be initiated by the relatively energetic self-loading process necessary to reliably chamber cartridges. Most military ammunition makes use of hard primers unlikely to be detonated by a comparatively light inertial strike.[3][4] The NATO military alliance uses NATO specific standardization agreements (STANAGs) that define the minimal and maximal allowed primer sensitivity for small arms ammunition. For 5.56×45mm NATO ammunition STANAG 4172, among a considerable number of technical requirements, specifies the permissible primer sensitivity range for 5.56×45mm NATO ammunition.[5]

Spring-loaded firing pins may move further forward than expected during the loading process if the restraining spring is broken or weakened by age. As rust, dirt, fouling, or inappropriately viscous lubricants accumulate in the firing pin channel, both free-floating and spring-loaded firing pins may be held in a forward position protruding from the bolt face. While rust prevention is important, wet lubricants can trap carbon and other pollutants from burning propellant, so avoidance of excess lubrication reduces the risk of slam fires from firing pins becoming stuck forward.[1]

Anything adhering to the tip of a firing pin or the portion of the bolt face behind the primer may cause unexpectedly heavy primer contact during the self-loading process. The larger priming compound distribution area of rimfire ammunition increases the number of locations where dirt or fouling on the bolt face or in the rim portion of the firearm chamber may deform the cartridge rim enough to function as a firing pin during the self-loading process.

Risks

[edit]

Unintended slamfires are dangerous, and recoil may cause shooters to lose control of light firearms with conditions causing sequential slamfires if a normally semi-automatic firearm "goes full-auto" unexpectedly.[6] A single defective cartridge may cause a single slamfire, but a firing pin stuck in a forward position or a magazine loaded with defective ammunition may cause a round to fire every time the bolt closes until the magazine is empty.

Shooters must keep the firearm pointed in a safe direction ("downrange") while closing the bolt and chambering a cartridge. If a slamfire does occur, the shooter must do his or her best to hold the firearm securely pointed in a safe direction until it ceases firing. This requires discipline, because untrained shooters may become surprised and instinctively drop the firearm as soon as it begins firing.

Aside from the dangers of any accidental discharge, an out-of-battery ignition may occur if a round slamfires before it is completely secured in the chamber. The firearm may be damaged or destroyed by a breech explosion potentially injuring the shooter and bystanders.[2]

Intentional slamfire designs

[edit]

Pipe guns use a free floating gun barrel with a rimmed cartridge (usually a shotgun shell) inserted in the breech, sliding within a pipe functioning as a tubular receiver with a fixed firing pin in the back. No trigger or lockwork is required, because the loaded barrel is simply inserted into the pipe and slammed backward to fire.[7] Some use improvised detachable magazines.[8]

See also

[edit]

References

[edit]
  1. 1 2 Johnson, Melvin M. (1944). Rifles and Machine Guns. New York: William Morrow and Company. pp. 352–357.
  2. 1 2 "Reloading for Semi-Autos and Service Rifles". Exterior Ballistics. Archived from the original on 28 January 2019. Retrieved 8 February 2019.
  3. ↑ "Collecting and Shooting the Military Surplus Rifle (2006) - Surplusrifle.com". Surplusrifle.com. Archived from the original on 2008-11-03. Retrieved 2008-09-06.
  4. ↑ "CCI Military Rifle Primers". CCI. Retrieved 2009-03-04. [dead link]
  5. ↑ "STANAG 4172 5.56 mm ammunition (linked or otherwise)" (PDF). Archived (PDF) from the original on 2020-11-12. Retrieved 2020-11-18.
  6. ↑ Beckhusen, Robert (February 10, 2020). "The SKS Is a Clunker That Just Won't Die". The National Interest. Archived from the original on February 11, 2020. Retrieved February 10, 2020.
  7. ↑ "Homemade 12 Gauge Slamfire Guns!!!". YouTube. Archived from the original on 2016-09-16. Retrieved 2016-09-26.
  8. ↑ Gordon Dahle (November 10, 2023). "Homemade Slam-Fire Shotgun with Detachable Magazine". YouTube. Archived from the original on November 25, 2023.

Source: Wikipedia. Article content is retrieved live through the MediaWiki API.

Wikipedia

Slamfire

A slamfire is a discharge of a firearm occurring as soon as a cartridge is being loaded into the chamber. Some firearms are designed to slamfire, but the term also describes a malfunction of self-loading firearms. Shooters accustomed to firearms requiring trigger activation for discharge may be unprepared for a slamfire discharge. Some military firearms are designed to fire from an open bolt condition to avoid the unintended discharge of a chambered cartridge cooking off in a gun barrel heated by firing previous cartridges. Activating the trigger of such firearms releases the spring-loaded bolt to move forward stripping a cartridge from the magazine into the chamber. The firing pin impacts the primer as the cartridge is chambered, and the energy released by the discharging cartridge returns the bolt into an open position while ejecting the empty case.

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Wikipedia

Unintentional discharge

An unintentional discharge is the event of a firearm discharging (firing) at a time not intended by the user. An unintended discharge may be produced by an incompatibility between firearm design and usage, such as the phenomenon of cooking off a round in a closed bolt machine gun, a mechanical malfunction as in the case of slamfire in an automatic weapon, or be user induced due to training issues or negligence. The phenomenon has also been defined in scientific literature as an activation of the trigger mechanism that results in an unplanned discharge that is outside of the firearm’s prescribed use, where "prescribed use" refers to departmental policies and laws related to the operation of firearms (O'Neill, 2018).

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Wikipedia

Mainspring (firearms)

In firearms, the mainspring is a spring in the firing mechanism which stores the energy required to ignite the primer of the cartridge. The mainspring may be called a striker spring on striker-fired firearms, or hammer spring on hammer-fired firearms. After the trigger mechanism has been released, the tensioned mainspring will drive the firing pin or hit the firing pin so that it is driven. Mainsprings can come in many shapes, such as a cylindrical spring (Mosin-Nagant, TT-33, Colt M1911), plate spring (Nagant revolver model 1895, Makarov pistol) or spiral spring (Kalashnikov). On a number of automatic firearms, the recoil spring may also function as a mainspring (FN Browning M1900, Degtyaryov machine gun, and some submachine guns). Mainsprings should not be confused with the type of firing pin spring which is utilised in some designs instead of free-floating firing pins to prevent slamfire.

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Wikipedia

Turtle Rock Studios

Turtle Rock Studios (known as Valve South between 2008 and 2010) is an American video game developer founded in March 2002 by Mike Booth. It was acquired by Valve in 2008, but was re-founded in 2010 as a subsidiary of Slamfire Inc. by Phil Robb and Chris Ashton. Turtle Rock Studios is involved in the creation of original titles as well as the provision of consulting services to the digital entertainment industry. The company's most notable games are: the first Left 4 Dead, which was published by Valve; Evolve, which was originally set to be published by THQ but was later published by 2K Games; and Back 4 Blood, which was published by Warner Bros. Games. The founder of the company had worked for Westwood Pacific, and assisted in the development of the Counter-Strike series. The company expanded from six employees to more than seventy staff members from 2011 to 2014 and opened a subsidiary company called Turtle Rock Garage in 2011, which specialized in developing casual and experimental games for platforms such as iPhone, Facebook, and Xbox Live. Tencent acquired the company in December 2021.

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TOPIC OF THE DAY

Greenwood / Black Wall Street

Before the 1921 destruction of Tulsa’s Greenwood District, Black residents had created a remarkable center of business and community life. The district included stores, professional offices, entertainment venues and homes owned by Black citizens. Understanding Greenwood means learning what was built—not only what was burned.

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TRIVIA QUESTION OF THE DAY

Which Supreme Court case ruled state-sponsored public-school segregation unconstitutional?

Brown v. Board of Education in 1954.