Comments by "" (@neutronalchemist3241) on "How Does it Work: Gas-Delayed Blowback" video.

  1. In a delayed blowback gun, ANY system (roller, lever, radial, gas...) the bolt/slide starts to travel rearwards the same moment the round is fired. The delay only makes so that the movement is slow enough that the bullet exits from the barrel before the case had been stretched enough to break it (the function that the simple mass of the bolt has in a pure blowback system). Then, in the case of the first gun shown here (the Steyr GB) it’s rather questionable if an opening half way through the barrel, from where the spilled gas has to fill a relatively large space can really act to delay the opening of the action until pressure drops to safe level. Probably it acts just like a buffer, preventing the slide to slam into the frame at a speed dangerous for the integrity of the gun (and detrimental for the comfort of the shooter), while the action is largely a pure blowback.
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  2. It’s rather questionable if an opening half way through the barrel, from where the spilled gas has to fill a relatively large space (like in the first pistol shown) can really act to delay the opening of the action until pressure drops to safe level. Probably it acts just like a buffer, preventing the slide to slam into the frame at a speed dangerous for the integrity of the gun (and detrimental for the comfort of the shooter), while the action is largely a pure blowback.
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