Understanding Theory

Yes, it can be legal to make a silencer. For everything Form-1, from silencer designs that are easily made, to filing forms with the BATF, to 3D modeling. Remember, you must have an approved BATF Form-1 to make a silencer. All NFA laws apply.

Moderators: mpallett, bakerjw

Post Reply
Matt in TN
Silent Operator
Posts: 87
Joined: Tue Jun 09, 2015 9:11 am

Understanding Theory

Post by Matt in TN »

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?
22: http://www.silencertalk.com/forum/viewtopic.php?t=138952
30: http://www.silencertalk.com/forum/viewtopic.php?f=10&t=156481
9: http://www.silencertalk.com/forum/viewtopic.php?f=10&t=696697
User avatar
doubloon
Silent But Deadly
Posts: 11897
Joined: Wed Dec 31, 2008 11:02 pm
Location: Houston-ish

Re: Understanding Theory

Post by doubloon »

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
User avatar
whiterussian1974
Silent But Deadly
Posts: 2857
Joined: Sat Sep 28, 2013 11:37 pm
Location: On 8th line of eye chart.

Re: Understanding Theory

Post by whiterussian1974 »

"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
silencertalk.com/forum/viewtopic.php?f=10&t=135314
Matt in TN
Silent Operator
Posts: 87
Joined: Tue Jun 09, 2015 9:11 am

Re: Understanding Theory

Post by Matt in TN »

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.
22: http://www.silencertalk.com/forum/viewtopic.php?t=138952
30: http://www.silencertalk.com/forum/viewtopic.php?f=10&t=156481
9: http://www.silencertalk.com/forum/viewtopic.php?f=10&t=696697
FarmDadCO
Member
Posts: 33
Joined: Sat May 31, 2014 7:11 pm

Re: Understanding Theory

Post by FarmDadCO »

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.
User avatar
whiterussian1974
Silent But Deadly
Posts: 2857
Joined: Sat Sep 28, 2013 11:37 pm
Location: On 8th line of eye chart.

Re: Understanding Theory

Post by whiterussian1974 »

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
silencertalk.com/forum/viewtopic.php?f=10&t=135314
Matt in TN
Silent Operator
Posts: 87
Joined: Tue Jun 09, 2015 9:11 am

Re: Understanding Theory

Post by Matt in TN »

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!
22: http://www.silencertalk.com/forum/viewtopic.php?t=138952
30: http://www.silencertalk.com/forum/viewtopic.php?f=10&t=156481
9: http://www.silencertalk.com/forum/viewtopic.php?f=10&t=696697
User avatar
doubloon
Silent But Deadly
Posts: 11897
Joined: Wed Dec 31, 2008 11:02 pm
Location: Houston-ish

Re: Understanding Theory

Post by doubloon »

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
Post Reply