Engineering Study

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.

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bigb6456
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Engineering Study

Post by bigb6456 »

Hello,

I'm working on the start of an engineering study about suppressors, I was wondering if anyone can point me in the right direction for information gathering. I'm looking for information on current or relatively current designs.
I'm looking for books with detailed information & cad files to start with.

Yes I'm aware of all the laws and no I'm not looking for these items to build a suppressor.
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Dr.K
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Re: Engineering Study

Post by Dr.K »

Good luck. That seems to be on par with "Who shot Kennedy?"

I've seen it asked before. Most of it is relatively TOP SECRET or something. Lot's of pics/ drawings, but very little in the actual science realm that is not internal to whatever company. This forum is pretty much best I've found as far as actual modern research. There are some books, but they are old and kind of outdated.
Kyle O.
bigb6456
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Re: Engineering Study

Post by bigb6456 »

Thanks for the fast reply,

I like the analogy of JFK, I love how companies like to make things so cloak and dagger. A suppressor is like Mayo while many companies make mayo and like to think they have the super secret to it; in the end it's just eggs and oil and vinegar.
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Capt. Link.
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Re: Engineering Study

Post by Capt. Link. »

bigb6456 wrote:Hello,

I'm working on the start of an engineering study about suppressors, I was wondering if anyone can point me in the right direction for information gathering. I'm looking for information on current or relatively current designs.
I'm looking for books with detailed information & cad files to start with.

Yes I'm aware of all the laws and no I'm not looking for these items to build a suppressor.
Why a suppressor works is firmly seated in science.The hocus pocus is mostly BS that company's advertize to lure gullible people into buying what there company sells over the competition.The top secret part is protecting a company's research from people that will copy the hard work they have done.You will not find any hard copy of what you seek because of this.Here is a route to enlightenment that is open to you.
You can start your research with the study of the ideal gas laws and then the nature of sound and how it is measured and perceived.The study of industrial suppressors and similar work will give you some incite on the hows and whys one design may out perform another under the same conditions.A study of thermodynamics is useful as is other related areas of study.After 30 years of research and gathering data I have learned that size dose not matter but the total effect in handling all of the variables of a gas and the perception of sound dose.
You should apply for a tax stamp and build a working model to validate your study.
Good Hunting.
The only reason after 243 years the government now wants to disarm you is they intend to do something you would shoot them for!
http://www.silencertalk.com/forum/viewtopic.php?f=10&t=79895
bigb6456
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Re: Engineering Study

Post by bigb6456 »

Thank you Capt.

It sounds more like physics then engineering. I don't have machines to make one so filing for a tax stamp would be a waste.
Historian
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Re: Engineering Study

Post by Historian »

bigb6456 wrote:Thank you Capt.

It sounds more like physics then engineering. I don't have machines to make one so filing for a tax stamp would be a waste.
Actually it is physics/engineering analogous to
Space/Time. Inseparable. Real physics as the cognoscenti know deals with
subjects such as Quantum Electro-dyanamics, Prions, 8-Fold Way, Quantum
Gravity, etc. And the mathematics is so far up the 'stratosphere' such as
Riemann Differentiable Manifolds, Tensor Algebra, etc.

The above is a way of saying that the Capt. is spot on. It is the fundamental language
to capture, articulate, design, measure, and experiment with. Famous line
a Greek Mathematician told a Royal Pupil: "There is no royal road to geometry".

Or as in the 1960's when a student was told that to learn Karate would take
10 years of intense dedication, focus, and study he responded that he wanted to
learn to break boards and go into a biker bar and defend himself.

He was taught to break boards in 10 minutes ... and then saw the Dans working out.
A mega-oops caused a light bulb to go on. 45 years later he is a master teacher and
never went into that mental onanistic biker bar without his SWAT team back up. :)

A possible study syllabus:

1. Review all the past postings on this site on Silencer Smithing.

2. Purchase:

a. "SILENCERS -PRINCIPLES AND EVALUATIONS", DEPT. ARMY FRANKFORD ARSENAL,
Philadelphia, Pa. 19137, Report R-1896, August 1968

b. "Firearm Silencers", Vol. 1, US by Donald B. McLean, NORMOUNT ARMAMENT CO.
Forest Grove, Oregon.

3. Visit all sites where discussions are made.

4. Listen to the Sensei here, The Good Captain, Mr. B, Enfield, etc.

Good luck, ask questions.
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doubloon
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Re: Engineering Study

Post by doubloon »

bigb6456 wrote:...
I'm looking for books with detailed information & cad files to start with.
...
Good luck on books and cad files.

In my sig is a link to the completed form 1 build thread on this site, an excellent source of information.

Also a good source for take apart cans is all the instructional videos out there on how to break them down and clean them.
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
bigb6456
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Re: Engineering Study

Post by bigb6456 »

doubloon wrote:
bigb6456 wrote:...
I'm looking for books with detailed information & cad files to start with.
...
Good luck on books and cad files.

In my sig is a link to the completed form 1 build thread on this site, an excellent source of information.

Also a good source for take apart cans is all the instructional videos out there on how to break them down and clean them.

Ah your first youtube link is to the most disturbing thing ever, thanks I now need therapy & thank god your second youtube link didn't work because god only knows what it was for.
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Re: Engineering Study

Post by Fulmen »

Capt. Link. wrote:Why a suppressor works is firmly seated in science.The hocus pocus is mostly BS
I agree, the physics involved is fairly well understood. But that doesn't make it simple to design a good silencer, while we may understand the physics we're still talking about a highly complex system that requires serious computational power to simulate properly. And understanding the physics doesn't automatically tell you the optimum solution to a problem, often you are reduced to trying out ideas to see how they work.

So even with all the knowledge and simulation tools available you basically need to work up experience by trial&error.
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doubloon
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Re: Engineering Study

Post by doubloon »

bigb6456 wrote:...
Ah your first youtube link is to the most disturbing ...
Well, the build link was clearly marked and a thread not a video. :mrgreen:

I think the second link was to an popular and inspiring commencement speech that has been removed for likely less than inspiring reasons.
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
Historian
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Re: Engineering Study

Post by Historian »

Fulmen wrote:
Capt. Link. wrote:Why a suppressor works is firmly seated in science.The hocus pocus is mostly BS
I agree, the physics involved is fairly well understood. But that doesn't make it simple to design a good silencer, while we may understand the physics we're still talking about a highly complex system that requires serious computational power to simulate properly. And understanding the physics doesn't automatically tell you the optimum solution to a problem, often you are reduced to trying out ideas to see how they work.

So even with all the knowledge and simulation tools available you basically need to work up experience by trial&error.
+1!

That is where the real science and fun, measured/delimited by nature's pain in the butt
restrictions, begins.

As Thomas - 'I will patent anything my staff discovers under my name' - Edison said:
10% inspiration, 90% perspiration.
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Re: Engineering Study

Post by pnl2012 »

Try & Error R&D is a lot cheaper for the Smaller size Markets; like Suppressors. All you have to do is figure out, build and try. Not for individuals in USA since you have to pay 200 dollars tax per build. However, it’s not impossible to fully and accurately simulate a Suppressed Gun Shot. It’s just too expensive in terms of Computing Power (like Fullmen highlights). It’s been done before at some European Universities using simple Baffle shapes but not being most Universities “Gun friendly” it’s quite difficult to find “cheap” CPU time for more complex systems and/or higher density meshes. If you still want to dig on to the MultiPhisics Gun Shot models, check this out, it’s a good starting point: http://www.aos.sk/casopisy/science/doku ... 1/cl11.pdf
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unclemoak
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Re: Engineering Study

Post by unclemoak »

This thread is of interest to my new found desire in building a Form 1 can.
Engineer looking for a new job, PM me
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Re: Engineering Study

Post by Historian »

pnl2012 wrote:Try & Error R&D is a lot cheaper for the Smaller size Markets; like Suppressors. All you have to do is figure out, build and try. Not for individuals in USA since you have to pay 200 dollars tax per build. However, it’s not impossible to fully and accurately simulate a Suppressed Gun Shot. It’s just too expensive in terms of Computing Power (like Fullmen highlights). It’s been done before at some European Universities using simple Baffle shapes but not being most Universities “Gun friendly” it’s quite difficult to find “cheap” CPU time for more complex systems and/or higher density meshes. If you still want to dig on to the MultiPhisics Gun Shot models, check this out, it’s a good starting point: http://www.aos.sk/casopisy/science/doku ... 1/cl11.pdf
Excellent paper. Thank you for finding and
pointing it out.
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Capt. Link.
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Re: Engineering Study

Post by Capt. Link. »

The statement has been made that a engineering study is being contemplated. What is the scope of the study and what will be used for information or validation.The computational analysis is a bust and next to nothing is in print,without working models and test equipment I can't see any scientific information being gained.What are your attempting to study and how.
The only reason after 243 years the government now wants to disarm you is they intend to do something you would shoot them for!
http://www.silencertalk.com/forum/viewtopic.php?f=10&t=79895
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Re: Engineering Study

Post by Grounded »

pnl2012 wrote:Try & Error R&D is a lot cheaper for the Smaller size Markets; like Suppressors. All you have to do is figure out, build and try. Not for individuals in USA since you have to pay 200 dollars tax per build. However, it’s not impossible to fully and accurately simulate a Suppressed Gun Shot. It’s just too expensive in terms of Computing Power (like Fullmen highlights). It’s been done before at some European Universities using simple Baffle shapes but not being most Universities “Gun friendly” it’s quite difficult to find “cheap” CPU time for more complex systems and/or higher density meshes. If you still want to dig on to the MultiPhisics Gun Shot models, check this out, it’s a good starting point: http://www.aos.sk/casopisy/science/doku ... 1/cl11.pdf

I gave it a crack in both ansys and comsol and the processing power for mach flow with particulate was still requiring weeks and weeks for the simulation to run.
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Re: Engineering Study

Post by gunny50 »

Grounded wrote:

I gave it a crack in both ansys and comsol and the processing power for mach flow with particulate was still requiring weeks and weeks for the simulation to run.

well most of the time Form 1's are not approved in a few days so that should NOT hold you back in running it.

Gunny
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Re: Engineering Study

Post by Armorer-at-Law »

You can learn a lot about various designs by searching patents. Try Google Patents, uspto.gov, and/or worldwide.espacenet.com.

But remember, just because it patented doesn't mean it's better and not all of the most current designs are patented. Some manufacturers use very traditional baffle types on some models and the innovation is in the "fine tuning" that is maintained as trade secret and difficult to reverse-engineer.
Send lawyers, guns, and money...
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Re: Engineering Study

Post by Grounded »

gunny50 wrote:
Grounded wrote:

I gave it a crack in both ansys and comsol and the processing power for mach flow with particulate was still requiring weeks and weeks for the simulation to run.

well most of the time Form 1's are not approved in a few days so that should NOT hold you back in running it.

Gunny
Form 1's lol.
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Re: Engineering Study

Post by gunny50 »

Grounded wrote:
gunny50 wrote:
Grounded wrote:

I gave it a crack in both ansys and comsol and the processing power for mach flow with particulate was still requiring weeks and weeks for the simulation to run.

well most of the time Form 1's are not approved in a few days so that should NOT hold you back in running it.

Gunny
Form 1's lol.

Geeee Grounded, ;-)

we all know what I was referring to.

Over here all that paper work is not a problem, one can have them or one can not. just that simple.

But still computer time is computer time, personally I would run it as accurate as possible even if it would take a few weeks.

gunny
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Re: Engineering Study

Post by pnl2012 »

“Weeks” is just for testing a Blast design or for testing a 1:4 scaled (or more) Suppressor. I have a full Suppressor COMSOL model running now, 1:2 and it’s 30% done after 3 months. No way, just keeping that batch for my thesis because I have to argue and document but since I found out 3D Printing, I go faster and cheaper. The only issue with try & error is that you never know why it does or it doesn’t work …
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Re: Engineering Study

Post by Hard_ware »

Physics plain and simple. Keep in mind that not only sound will give you away. As far as suppressors for supersonic rounds look at all the brands sold and all I have seen are under -40db reduction so no magic usually around 35-38db. When trying to achieve silent shooting it all starts in the powder, grains of projectile being push and velocity looking to achieve within the barrel length being used, again physics plain and simple. The active method of generating a sound wave 180 degrees out of phase to cancel the sound being created and reducing the sound even further has yet to be seen (that I am aware of and I don't know much but always willing to learn), or generating sound above the hearing range of the human ear. The energy has to go somewhere, different densities of materials transmit sound at different resonate frequencies again all in the physics. The modeling software is only as good as the parameters the programmer is able to constrain, real world is where it's at. No magic! size does matter! But being bigger does not make it better if it is poorly designed. Products on the market that are commercially successful appear to be the smaller,with ~ -35db in sound reduction but they emit a flame at night that gives you away! . Do your due diligence, thermal dynamics, sound propagation, engineering (chemical as well as physical) if you are loading your own ammo, a lot to think about. But getting into the -30db range can be done with tail pipe and freeze plugs (<$50 + form 1 $200= $250 if in the USA) no titanium or inconel necessary! :D

on a tangent, new items added to Trusts are going to be needing finger prints and photos sent in thanks to Obama in the very near future!
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Re: Engineering Study

Post by Grounded »

pnl2012 wrote:“Weeks” is just for testing a Blast design or for testing a 1:4 scaled (or more) Suppressor. I have a full Suppressor COMSOL model running now, 1:2 and it’s 30% done after 3 months. No way, just keeping that batch for my thesis because I have to argue and document but since I found out 3D Printing, I go faster and cheaper. The only issue with try & error is that you never know why it does or it doesn’t work …
My wife always yells at me for understating things. I say grab a couple and I mean ten, she brings two.

A lot of the design in my opinion is the application of theories. You can try and quantify them however you want but there has to be a limit. While in school its one thing as resources are essentially free and its a matter of you spending your time. In the work environment I need to consider how much time (aka money) I want to invest in development of a device that has the potential for miniscule civilian sales and next to impossible military sales.
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Re: Engineering Study

Post by Grounded »

Hard_ware wrote:Physics plain and simple. Keep in mind that not only sound will give you away. As far as suppressors for supersonic rounds look at all the brands sold and all I have seen are under -40db reduction so no magic usually around 35-38db. hat are commercially successful appear to be the smaller,with ~ -35db in sound reduction but they emit a flame at night that gives you away!
Ive tested many commercially available suppressors and I have yet to see one get -40dB. After All unsuppressed, in open air, 1 meter to the left of the muzzle your metering at 175dB. In this condition the most recent test of a suppressor that is a favorite of many here was only at 149dB...(-26dB)... and thats not on some hokey mic setup either.
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Re: Engineering Study

Post by Hard_ware »

Grounded wrote:
Hard_ware wrote:Physics plain and simple. Keep in mind that not only sound will give you away. As far as suppressors for supersonic rounds look at all the brands sold and all I have seen are under -40db reduction so no magic usually around 35-38db. hat are commercially successful appear to be the smaller,with ~ -35db in sound reduction but they emit a flame at night that gives you away!
Ive tested many commercially available suppressors and I have yet to see one get -40dB. After All unsuppressed, in open air, 1 meter to the left of the muzzle your metering at 175dB. In this condition the most recent test of a suppressor that is a favorite of many here was only at 149dB...(-26dB)... and thats not on some hokey mic setup either.
Yes, what I am pointing out is none have achieved the -40db mark that I am aware of. I have not tested them to even verify they reduce what mfg have stated. But the mid -30db range seems like the top of the line so far.
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