AlMgSi 5.0 pipe for a bolt action mechanism?
- FighterAce
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I've been searching for the best outer pipe for my bolt action breech loading mechanism. I found an Aluminum pipe 25x2.5 -> 20mm ID witch is perfect for a 3/8 threaded coupling.
I'm just not sure if this aluminum alloy AlMgSi5.0 would be adequate for the task.
Operating pressure of the gun would be around 40 bar, caliber 13mm.
In case your wondering why I need the 3/8 coupling to fit in the Al pipe.... its because 15mm OD copper pipe can thread into the coupling with a little bit of PTFE - no threads on the copper needed for a snug fit.
I'm just not sure if this aluminum alloy AlMgSi5.0 would be adequate for the task.
Operating pressure of the gun would be around 40 bar, caliber 13mm.
In case your wondering why I need the 3/8 coupling to fit in the Al pipe.... its because 15mm OD copper pipe can thread into the coupling with a little bit of PTFE - no threads on the copper needed for a snug fit.
“The combined synergy of a man and rifle is matchless.
The steadiness of hand, the acuity of vision and finally
the art of knowing how to make the rifle an extension of the
body all equate to the ultimate synthesis of man and machine.”
The steadiness of hand, the acuity of vision and finally
the art of knowing how to make the rifle an extension of the
body all equate to the ultimate synthesis of man and machine.”
- FighterAce
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I thought there are some people here that are into aluminum pipes... guess I was wrong 
Tisk, tisk, tisk.

Tisk, tisk, tisk.
“The combined synergy of a man and rifle is matchless.
The steadiness of hand, the acuity of vision and finally
the art of knowing how to make the rifle an extension of the
body all equate to the ultimate synthesis of man and machine.”
The steadiness of hand, the acuity of vision and finally
the art of knowing how to make the rifle an extension of the
body all equate to the ultimate synthesis of man and machine.”
- Labtecpower
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this is the first time I read this.
Mg makes the aluminium harder and more durable. I think Si does the same. I think this pipe is better for the purpose than just plain aluminium.
40 bars should be perfectly safe.
Mg makes the aluminium harder and more durable. I think Si does the same. I think this pipe is better for the purpose than just plain aluminium.
40 bars should be perfectly safe.
- FighterAce
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Thank you Labtecpower.
Sorry jrrdw... its the first time I ever did it and you immediately jump on it like I don't know its wrong....
I need to buy the pipe this week and people were not noticing the thread. And yes I called the store to try and get the explanation but the guy I got on the phone just knew it contained magnesium and silicone. Not what it does to the aluminum. What would you do in my position? Wait and miss the opportunity? Or walk to the first person on the street and ask him? lol
Sorry jrrdw... its the first time I ever did it and you immediately jump on it like I don't know its wrong....
I need to buy the pipe this week and people were not noticing the thread. And yes I called the store to try and get the explanation but the guy I got on the phone just knew it contained magnesium and silicone. Not what it does to the aluminum. What would you do in my position? Wait and miss the opportunity? Or walk to the first person on the street and ask him? lol
“The combined synergy of a man and rifle is matchless.
The steadiness of hand, the acuity of vision and finally
the art of knowing how to make the rifle an extension of the
body all equate to the ultimate synthesis of man and machine.”
The steadiness of hand, the acuity of vision and finally
the art of knowing how to make the rifle an extension of the
body all equate to the ultimate synthesis of man and machine.”
- jrrdw
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I would 1st ask the seller where they get it from, then go to the supplier and get the manufactures name and company information. 2nd I would contact the manufacture and get a data sheet on their product. If I couldn't get my information that way......GOOGLE IS YOUR FRIEND!
Our friend Google says start here.

Our friend Google says start here.
- FighterAce
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Google is first thing I tried... I got the desired result only after I entered the detail that Labtecpower kindly shared with me.
They ARE the manufacturer. You wouldn't believe what kind of things are going on in my country! I wouldn't be surprised if they hired a waste collector; that just had his primary school behind him; to work in a school.
Putting a guy behind the phone that has no idea what the factory is doing is nothing.
I must admit you seem arrogant. You therefor must be intelligent. You wouldn't be a moderator otherwise
Time to say "Stay on Topic!" ?
They ARE the manufacturer. You wouldn't believe what kind of things are going on in my country! I wouldn't be surprised if they hired a waste collector; that just had his primary school behind him; to work in a school.
Putting a guy behind the phone that has no idea what the factory is doing is nothing.
I must admit you seem arrogant. You therefor must be intelligent. You wouldn't be a moderator otherwise

Time to say "Stay on Topic!" ?
“The combined synergy of a man and rifle is matchless.
The steadiness of hand, the acuity of vision and finally
the art of knowing how to make the rifle an extension of the
body all equate to the ultimate synthesis of man and machine.”
The steadiness of hand, the acuity of vision and finally
the art of knowing how to make the rifle an extension of the
body all equate to the ultimate synthesis of man and machine.”
- FighterAce
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That... came out kinda wrong I didn't want to say you're intelligent just because the way you express yourself but what you actually say... I guess?
So its more sort of a compliment...
I've seen that color before! What do you give to guys that triple post? 3 tisks?
So its more sort of a compliment...
I've seen that color before! What do you give to guys that triple post? 3 tisks?
“The combined synergy of a man and rifle is matchless.
The steadiness of hand, the acuity of vision and finally
the art of knowing how to make the rifle an extension of the
body all equate to the ultimate synthesis of man and machine.”
The steadiness of hand, the acuity of vision and finally
the art of knowing how to make the rifle an extension of the
body all equate to the ultimate synthesis of man and machine.”
Doesn't Si in this instance stand for silicon, not silicone?FighterAce wrote:magnesium and silicone
- FighterAce
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Indeed it doessaefroch wrote:Doesn't Si in this instance stand for silicon, not silicone?

“The combined synergy of a man and rifle is matchless.
The steadiness of hand, the acuity of vision and finally
the art of knowing how to make the rifle an extension of the
body all equate to the ultimate synthesis of man and machine.”
The steadiness of hand, the acuity of vision and finally
the art of knowing how to make the rifle an extension of the
body all equate to the ultimate synthesis of man and machine.”
- Labtecpower
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In case you mean silicon greadse, that wouldn't add to the quality of the aluminium. 

The lowest yield strength I was able to find anywhere, for any AlMgSi alloy was 90 MPa. Given that, and the dimensions of your pipe, that leaves you a safety factor of ~5 when operating at 40 bar.
However, I was not able to find any information on your particular alloy. There are a few members on here with a good deal of metallurgical knowledge who might be able to help out on this one. I suspect that it'll be fine in terms of yield pressure alone, but I can't say much beyond that.
However, I was not able to find any information on your particular alloy. There are a few members on here with a good deal of metallurgical knowledge who might be able to help out on this one. I suspect that it'll be fine in terms of yield pressure alone, but I can't say much beyond that.
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- Labtecpower
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an alloy consisting of magnesium and aluminium is called magnalium.
(with your explosive interests you should know, DYI, altough I doubt its functionality in HE's)
I'm not sure about the Silicon yet... I think it has something to do with the hardness and strength.
I read reports of magnalium for pyro uses, consisting of 50/50 Mg Al,
That was so hard it shattered in an obsidian-like way. If it wasn't so brittle, it would make an acceptable knive material.
(with your explosive interests you should know, DYI, altough I doubt its functionality in HE's)
I'm not sure about the Silicon yet... I think it has something to do with the hardness and strength.
I read reports of magnalium for pyro uses, consisting of 50/50 Mg Al,
That was so hard it shattered in an obsidian-like way. If it wasn't so brittle, it would make an acceptable knive material.
- FighterAce
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I'm not going to be filling this pipe with air. It will only be the outer pipe for a bolt action and I guess there are different stresses involved in that during the firing.DYI wrote:The lowest yield strength I was able to find anywhere, for any AlMgSi alloy was 90 MPa. Given that, and the dimensions of your pipe, that leaves you a safety factor of ~5 when operating at 40 bar.

But it sounds very good... 5x safety factor, potentially even more. I could actually cut threads into the pipe and use it as a chamber down the road when I get my hands on some bigger machines, tools and - higher pressure.
“The combined synergy of a man and rifle is matchless.
The steadiness of hand, the acuity of vision and finally
the art of knowing how to make the rifle an extension of the
body all equate to the ultimate synthesis of man and machine.”
The steadiness of hand, the acuity of vision and finally
the art of knowing how to make the rifle an extension of the
body all equate to the ultimate synthesis of man and machine.”