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safewaysecurity
06-21-2010, 4:31 PM
What is the function of the gasport and gas tube in an ar-15?

xLusi0n
06-21-2010, 4:36 PM
Cycles the bolt.

safewaysecurity
06-21-2010, 4:39 PM
How? Where does the gas come from? I really have no idea.

Droppin Deuces
06-21-2010, 4:39 PM
http://www.bushmaster.com/anatomy_bushmaster.asp

Edit: I guess that doesn't actually show how the gas cycles the bolt, but it's still cool to look at and click on the different stuff.

Droppin Deuces
06-21-2010, 4:43 PM
http://www.adamsarms.net/content.asp?content=10


Click on the first video.

safewaysecurity
06-21-2010, 4:44 PM
The thing you linked showed me what I thought. I thought the inital discharge of the cartridge cycled the bolt..

safewaysecurity
06-21-2010, 4:47 PM
Thanks that video really helped.

Ishoot
06-21-2010, 4:48 PM
What is the function of the gasport and gas tube in an ar-15?

It diverts some of the gases from the combustion of the powder in the round. Ya know, the "gases" that propel the bullet to the target. :) That diverted gas then unlocks the bolt and cycles it rearward, ejecting the cartridge and cocking the hammer or pin.

Turo
06-21-2010, 4:49 PM
Gas is created from the combustion of the gunpowder contained in the cartridge. When that powder ignites, it becomes gas which expands at a high rate of speed, and at very high pressures, driving the bullet down the barrel. The gas system in the AR collects a small part of that expanding gas, and uses it to drive the bolt back, in order to eject the casing and chamber a new round.

Don't worry if you don't know something, we all had to start somewhere. If you have any other questions, feel free to ask them :D.

Josh3239
06-21-2010, 5:22 PM
The thing you linked showed me what I thought. I thought the inital discharge of the cartridge cycled the bolt..

I believe that describes a blowback system like one found it a 10/22 Ruger. The AR15's actions are gas operated as how other members here have described.

Droppin Deuces
06-21-2010, 5:36 PM
I believe that describes a blowback system like one found it a 10/22 Ruger. The AR15's actions are gas operated as how other members here have described.

No, it's a DI system. It just didn't show the path and function of the gas as part of the animation.
The second link is an animation of the gas doing its thing.