blowback

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blowback

weaponry

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June 22, 2026

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Blowback is a term used to describe the fallout or ripple effect of an action. In the context of weaponry, specifically semiautomatic pistols and machine guns, blowback refers to a method of operation. In this system, the breechblock or bolt is not locked when the weapon is fired. Instead, the energy from the exploding cartridge thrusts the bolt backward, which ejects the spent cartridge and cocks the weapon for the next shot. This contrasts with recoil operation, where the bolt is locked to the barrel at the moment of firing. Blowback is a key principle in the design of many firearms, enabling their rapid, automatic firing capabilities.123

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AK-47
…and other forces known as blowback that were generated by the weapons’ heavy internal mechanisms. Those problems were partly addressed during the 1970s, when the AKM was replaced by the AK-74, which adapted the basic Kalashnikov design to a smaller 5.45-mm round with a higher muzzle velocity of 900 metres…
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…and other forces known as blowback that were generated by the weapons’ heavy internal mechanisms. Those problems were partly addressed during the 1970s, when the AKM was replaced by the AK-74, which adapted the basic Kalashnikov design to a smaller 5.45-mm round with a higher muzzle velocity of 900 metres…
Read More

semiautomatic pistol
…they most often employ the blowback mode of operation in which the breechblock or bolt is locked in firing position but is free to be thrust backward by the same burst of energy that propels the bullet forward. The rearward thrust ejects the spent cartridge from the chamber, while storing…
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…they most often employ the blowback mode of operation in which the breechblock or bolt is locked in firing position but is free to be thrust backward by the same burst of energy that propels the bullet forward. The rearward thrust ejects the spent cartridge from the chamber, while storing…
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submachine gun
Typically, expansion gases move a submachine gun bullet forward when the weapon is fired. The gases also push the heavy bolt back against a spring. The movement extracts and ejects the spent cartridge while the magazine spring pushes the next bullet into place. Holding the trigger…
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Typically, expansion gases move a submachine gun bullet forward when the weapon is fired. The gases also push the heavy bolt back against a spring. The movement extracts and ejects the spent cartridge while the magazine spring pushes the next bullet into place. Holding the trigger…
Read More