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Take a look at any parts diagram blow up. The lower houses the trigger and hammer assembly, and the magazine well. Nothing else. The buffer tube holds the deadblow buffer and recoil spring, the gaskey gets a shot of gas to work the breech bolt bolt carrier group, but that's very comparatively little pressure to do so. The gas from the gas tube under above the barrel blows the bolt carrier back and that rotates the bolt and pushes the bolt carrier and buffer back into the buffer tube back. The gas tube also is part of the upper assembly, which sees all the chamber pressure, gas tube pressure, and more.
Sounds like some people who own AR type rifles don't understand how they function.
 
Maybe he shoots his AR's hanging upside down by his knees and that's why he said the gas tube was under the barrel?

:s0092:
Apparently in his version the buffer tube gets a shot of hot gas and reciprocates. Sounds sexy
 
Well, her name is Mind and skullfricking is a thing, so....
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Apparently in his version the buffer tube gets a shot of hot gas and reciprocates. Sounds sexy
Hope you're having fun. I wouldn't be throwing stones if I was the guy who thought the lower had more pressure on it than the upper.
And yes, I'm not an AR guy, but I do own one. It rarely gets fired as I'm not enamored with them personally.
 
Hope you're having fun. I wouldn't be throwing stones if I was the guy who thought the lower had more pressure on it than the upper.
And yes, I'm not an AR guy, but I do own one. It rarely gets fired as I'm not enamored with them personally.
You're almost guaranteed to be the only person on this forum who thinks the way you do. Because it's incorrect. The upper receiver, as an individual component, absolutely does not bear more stress than the lower receiver. Lowers are known to break at specific locations mentioned earlier. Uppers are not known to break, almost at all.

And yes, I am having fun.
 
You're almost guaranteed to be the only person on this forum who thinks the way you do. Because it's incorrect. The upper receiver, as an individual component, absolutely does not bear more stress than the lower receiver. Lowers are known to break at specific locations mentioned earlier. Uppers are not known to break, almost at all.

And yes, I am having fun.

Why do lowers break in those places, exactly?
 
Hope you're having fun. I wouldn't be throwing stones if I was the guy who thought the lower had more pressure on it than the upper.
And yes, I'm not an AR guy, but I do own one. It rarely gets fired as I'm not enamored with them personally.
Your entire explanation was incorrect, but just keep digging. The upper receiver contains basically 0 pressure. It also wasn't a discussion of pressure it was a discussion of stress.

Why do lowers break in those places, exactly?
That's where recoil forces and handling forces are concentrated and they're generally pretty thin. It's not a problem in proper materials but problems show up when made with sub-optimal material properties.
 
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Why do lowers break in those places, exactly?
Because the combined weight of the buffer and bolt carrier slamming into the rear of the receiver extension/buffer tube repeatedly over time causes stress and eventually fractures which lead to total failure. The majority of those components live in or mostly transfer into the lower receiver assembly upon firing. The bolt carrier group lives within the upper receiver assembly, however it is not part of the upper.
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Your entire explanation was incorrect, but just keep digging. The upper receiver contains basically 0 pressure. It also wasn't a discussion of pressure it was a discussion stress.


That's where recoil forces and handling forces are concentrated and they're generally pretty thin. It's not a problem in proper materials but problems show up when made with sub-optimal material properties.
There's a reason cylinder heads and pistons are often made of aluminum but cylinders rarely, if ever, are. An upper that contained all tens of thousands of psi would explode before finishing a magazine. That's why when an AR kabooms, the upper goes kaput. It can't handle pressure. All that pressure is held in the steel components.
 
Imagine if the AR-15 was originally made with a steel receiver.
And somebody posted about finding an aluminum receiver!



The fighting! The insults! The rage!



Wait.................. We got that anyways. :s0114:
 
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