Primary extraction (original) (raw)
In breechloading firearms, primary extraction is the initial phase (the first few millimeters) of the extraction of a spent casing from the firearm chamber. After the primary extraction comes the secondary extraction where the bolt is moved further backwards, and the extraction is then normally finished with the spent cartridge being ejected.
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| dbo:abstract | In breechloading firearms, primary extraction is the initial phase (the first few millimeters) of the extraction of a spent casing from the firearm chamber. After the primary extraction comes the secondary extraction where the bolt is moved further backwards, and the extraction is then normally finished with the spent cartridge being ejected. The first few millimeters of extraction tend to require a much higher peak force than the rest of the extraction due to the spent casing sticking against the chamber walls. The sticking effect is a result from the case having expanded due to the high pressures during firing, and the extra initial force required can, depending on firearm design, make the extraction difficult for the user. Selfloading rifles usually don't have a separate motion for primary extraction, but instead depend on using a lot of force in order to start the extraction. Different designs are used for ensuring reliable extraction in manual mechanisms, with most of them being based on the principle of mechanical advantage. The camming action seen in many bolt-action rifles is an example of mechanical advantage being used for chambering and extraction. There are examples of some firearm designs being less successful due to poor design around the primary extraction, which can result in a stuck case in the chamber. Notably some pump and straight pull mechanisms are perceived as having the advantage over bolt actions that they are faster and require fewer body movements to operate by the user, however, they are often more complex than traditional bolt action designs, and often have little or no primary extraction lacking the mechanical advantage of a turn bolt which can lead to stoppages. There are some examples of straight pull and pump action rifles notorious for having extraction problems. Blaser R8 is a straight pull design which has been reported to have no issues with primary extraction. In this design, the bolt head moves in a purely linear motion, and except for the bolt handle cam when opening or closing the action, operation by the shooter is also purely linear. The Heym SR 30 is another successful design which features a bolt with ball bearings as locking elements. Here the primary extraction is performed by retracting the bolt handle, which uses leverage from the opposite side of the bolt to swing the handle to the open position, giving a mechanical advantage. (en) |
| dbo:thumbnail | wiki-commons:Special:FilePath/John_Olav_Ågotnes,_Sa...dsskytterstevnet_i_2008.jpg?width=300 |
| dbo:wikiPageExternalLink | https://www.longriflesinc.com/pages/services-primary-extraction-timing-tig-welding https://www.youtube.com/watch%3Fv=4cWnSmTeXWY https://www.youtube.com/watch%3Fv=ZFqOK843IyU |
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| dbo:wikiPageRevisionID | 1056170126 (xsd:integer) |
| dbo:wikiPageWikiLink | dbr:Blaser_R8 dbr:Mechanical_advantage dbr:List_of_pump-action_rifles dbr:Pump_action dbc:Firearm_terminology dbr:Force dbr:Breechloader dbr:Heym_SR_30 dbr:Bolt_(firearms) dbr:Cartridge_(firearms) dbr:Chamber_(firearms) dbr:Extractor_(firearms) dbr:List_of_straight-pull_rifles dbr:Bolt-action dbr:Firearm dbr:Straight-pull_rifles dbr:File:John_Olav_Ågotnes,_Sartor_Skytter...er_fra_landsskytterstevnet_i_2008.jpg dbr:File:Heym_SR_30_Straight_Pull_Bolt_Action.jpg |
| dbp:wikiPageUsesTemplate | dbt:Citation_needed dbt:Short_description |
| dct:subject | dbc:Firearm_terminology |
| rdfs:comment | In breechloading firearms, primary extraction is the initial phase (the first few millimeters) of the extraction of a spent casing from the firearm chamber. After the primary extraction comes the secondary extraction where the bolt is moved further backwards, and the extraction is then normally finished with the spent cartridge being ejected. (en) |
| rdfs:label | Primary extraction (en) |
| owl:sameAs | wikidata:Primary extraction dbpedia-no:Primary extraction https://global.dbpedia.org/id/9Nfk2 |
| prov:wasDerivedFrom | wikipedia-en:Primary_extraction?oldid=1056170126&ns=0 |
| foaf:depiction | wiki-commons:Special:FilePath/Heym_SR_30_Straight_Pull_Bolt_Action.jpg wiki-commons:Special:FilePath/John_Olav_Ågotnes,_Sa...er_fra_landsskytterstevnet_i_2008.jpg |
| foaf:isPrimaryTopicOf | wikipedia-en:Primary_extraction |
| is dbo:wikiPageDisambiguates of | dbr:Extraction |
| is dbo:wikiPageWikiLink of | dbr:Ross_rifle dbr:Extraction dbr:Blaser_R8 dbr:Breda_30 dbr:Remington_Model_7600 dbr:List_of_pump-action_rifles dbr:Mauser_M1996 dbr:Stoner_63 dbr:Type_99_light_machine_gun dbr:Vz._58 dbr:Garanin_general-purpose_machine_guns dbr:AA-52_machine_gun dbr:AK-47 dbr:AK-74 dbr:Heym_SR_30 dbr:International_Practical_Shooting_Confederation dbr:BMS_Cam_rifle dbr:Mannlicher_M1895 dbr:Bolt_action dbr:List_of_straight-pull_rifles |
| is foaf:primaryTopic of | wikipedia-en:Primary_extraction |
