Understanding Theory

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Matt in TN
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Understanding Theory

Post by Matt in TN » Mon Aug 17, 2015 11:25 pm

I've spent hours searching and reading here, and learned a lot already. What I haven't seen much of is a good explanation of the theoretical science behind various designs. For example - what are the flow characteristics of a K vs a cone baffle, and how does that contribute to suppression? And what does the porting or "mouse holes" really do and why/how?

I'm a licensed mechanical engineer that works with gas flow every day (although in MUCH lower temperatures and pressures!), and vaguely remember some of my fluid dynamics classes - but still have my books to refresh my memory. From what I understand though, very little of that applies as the fluid flow is closer to plasma and nothing like an ideal gas.

Is there a primer on suppressor design theory somewhere? Or is it all trial and error?

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doubloon
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Re: Understanding Theory

Post by doubloon » Tue Aug 18, 2015 8:02 am

R&D viewtopic.php?p=620637#p620637

People talk about Paulson's book a lot.

Synopsis from some threads on the topic ... K's and mouse holes work best for smaller, lower pressure calibers, stick with cones for the big, higher pressure calibers
http://www.youtube.com/watch?v=BDtd2jNIwAU MUSAFAR!
http://www.youtube.com/watch?v=8CrOL-ydFMI This is Water DavidW
Complete Form 1s http://www.silencertalk.com/forum/viewtopic.php?f=10&t=79895

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whiterussian1974
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Re: Understanding Theory

Post by whiterussian1974 » Tue Aug 18, 2015 11:36 am

"Does anyone have ideas for radical designs?"
viewtopic.php?f=10&t=123579&p=909419&hi ... al#p909419

And for the true Theoretician: http://www.grc.nasa.gov/WWW/K-12/Underg ... /index.htm
The Darkest Corners of Hell are reserved for those who remain Neutral!-Dante
The Death of One is a Tragedy, a million only a statistic.-Stalin
Well I AM 1/16 Demon on my Father's Side!-Dresden Files

Matt in TN
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Re: Understanding Theory

Post by Matt in TN » Tue Aug 18, 2015 2:46 pm

doubloon wrote: Synopsis from some threads on the topic ... K's and mouse holes work best for smaller, lower pressure calibers, stick with cones for the big, higher pressure calibers
Here's the issue - I'm trying to understand why and how the above seems to be true, not just if it is true!

Thanks for the link - that is a good thread, but it's all about the mechanical properties and calculating the pressures and wall thicknesses. That part I have a pretty good grasp on. I may have to get the Paulson book.

FarmDadCO
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Re: Understanding Theory

Post by FarmDadCO » Tue Aug 18, 2015 3:38 pm

Near as I can tell its pretty much reading the chicken bones and then applying the proper chant while you pray to the gods of the machine tool.

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whiterussian1974
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Re: Understanding Theory

Post by whiterussian1974 » Tue Aug 18, 2015 4:19 pm

No. My thread is about ideas more than formulae.

"Does anyone have ideas for radical designs?" viewtopic.php?f=10&t=123579&p=909419&hi ... al#p909419
I have a few others in the Smithing Section too. And Silencers (Frankford Arsenal report R-1896) is great reading. http://www.dtic.mil/dtic/tr/fulltext/u2/847383.pdf
It's my Anarch Cookbook for past designs and our tax $$$ paid for the research. :?
The Darkest Corners of Hell are reserved for those who remain Neutral!-Dante
The Death of One is a Tragedy, a million only a statistic.-Stalin
Well I AM 1/16 Demon on my Father's Side!-Dresden Files

Matt in TN
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Re: Understanding Theory

Post by Matt in TN » Tue Aug 18, 2015 11:27 pm

whiterussian1974 wrote:And Silencers (Frankford Arsenal report R-1896) is great reading. http://www.dtic.mil/dtic/tr/fulltext/u2/847383.pdf
It's my Anarch Cookbook for past designs and our tax $$$ paid for the research. :?
Now THAT is what I'm talking about! That looks like a great read to catch me up to 1974 technology.

I'm not ignoring your other thread - it'll just take me awhile to get through it all and be able to comment semi-intelligently. Thank you for posting those!

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doubloon
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Re: Understanding Theory

Post by doubloon » Tue Aug 18, 2015 11:43 pm

Matt in TN wrote:...
Here's the issue - I'm trying to understand why and how the above seems to be true, not just if it is true!
...
Mouse holes are one thing, Dater holes tend to turn some of the how and why on it's ear.

And this doesn't even touch on the art that is in some monocores.
http://www.youtube.com/watch?v=BDtd2jNIwAU MUSAFAR!
http://www.youtube.com/watch?v=8CrOL-ydFMI This is Water DavidW
Complete Form 1s http://www.silencertalk.com/forum/viewtopic.php?f=10&t=79895

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