Fluid Dynamics CAD Tools for Silencersmithing

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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calinb
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Fluid Dynamics CAD Tools for Silencersmithing

Post by calinb » Fri Jun 15, 2012 7:37 pm

While I continue to wait for my NFA stamps, would someone be kind enough to provide me with some links to tools or techniques or any other advice on how to get started with my own design investigations? Even comparing existing designs could be interesting.

Thanks!

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Bendersquint
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Re: Fluid Dynamics CAD Tools for Silencersmithing

Post by Bendersquint » Fri Jun 15, 2012 11:34 pm

calinb wrote:While I continue to wait for my NFA stamps, would someone be kind enough to provide me with some links to tools or techniques or any other advice on how to get started with my own design investigations? Even comparing existing designs could be interesting.

Thanks!
Research a bit on this forum and you will find out why Fluid Dynamics don't work with silencer design.

There are no tools or techniques for what you are looking for.

calinb
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Re: Fluid Dynamics CAD Tools for Silencersmithing

Post by calinb » Sat Jun 16, 2012 1:39 am

Bendersquint wrote:
calinb wrote:While I continue to wait for my NFA stamps, would someone be kind enough to provide me with some links to tools or techniques or any other advice on how to get started with my own design investigations? Even comparing existing designs could be interesting.

Thanks!
Research a bit on this forum and you will find out why Fluid Dynamics don't work with silencer design.

There are no tools or techniques for what you are looking for.
How about the pretty pictures with colored flows? Are they just for fun?

Historian
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Re: Fluid Dynamics CAD Tools for Silencersmithing

Post by Historian » Sat Jun 16, 2012 8:23 am

calinb wrote:
Bendersquint wrote:
calinb wrote:While I continue to wait for my NFA stamps, would someone be kind enough to provide me with some links to tools or techniques or any other advice on how to get started with my own design investigations? Even comparing existing designs could be interesting.

Thanks!
Research a bit on this forum and you will find out why Fluid Dynamics don't work with silencer design.

There are no tools or techniques for what you are looking for.
How about the pretty pictures with colored flows? Are they just for fun?
Most simple programs model continuous flows. The 'impulse' discharge in the internal ballistics in
a suppressor is stochastic ... so that actual real-time x-ray/Infrared experimentation still remains
the experimenter's best tool. One could imagine the difficulty trying to write a program to model shrapnel
and gasses from a grenade ... unless you have the new Chinese Mega-computer available to you.
Solving the many body problem will get someone a Noble Prize.

For example in the 1960's in the development of acoustic wave guides the optimum designs
came from a few folks born with a gut feeling from long term diddling of shapes. This is always
the case.

Testing a new design you might conceive and which might be the next break through, hopefully,
is the final decider. My favorite example of novel thinking was the Dardick tround. Ref WIKI for info.
Also see << http://www.youtube.com/watch?v=ifujl4j95TY >>.

Could the next generation suppressor be a 'Tround'-Tube so that the discontinuous
edges would further lower DB at the exit point? A triple of tround-cans mated together? Etc.

Do not let the lack of software deter you. I commend you for not wanting to limit your thinking.

Good luck.

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Bendersquint
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Re: Fluid Dynamics CAD Tools for Silencersmithing

Post by Bendersquint » Sat Jun 16, 2012 1:47 pm

calinb wrote:
Bendersquint wrote:
calinb wrote:While I continue to wait for my NFA stamps, would someone be kind enough to provide me with some links to tools or techniques or any other advice on how to get started with my own design investigations? Even comparing existing designs could be interesting.

Thanks!
Research a bit on this forum and you will find out why Fluid Dynamics don't work with silencer design.

There are no tools or techniques for what you are looking for.
How about the pretty pictures with colored flows? Are they just for fun?
For the most part yes, fluid dynamics can't accuratelly simulate gun powder gas flow. Gas is considered a fluid in fluid dynamics but it can not simulate gunpowder gas flow, its an entirely different beast.

calinb
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Re: Fluid Dynamics CAD Tools for Silencersmithing

Post by calinb » Sat Jun 16, 2012 4:07 pm

Historian wrote:... so that actual real-time x-ray/Infrared experimentation still remains
the experimenter's best tool.
...
Do not let the lack of software deter you. I commend you for not wanting to limit your thinking.
Thanks, Historian! I have some ideas, and I'm more deterred by the nearly long permission slip delays than the $200 price tag on each experiment!
Bendersquint wrote:For the most part yes, fluid dynamics can't accuratelly simulate gun powder gas flow.
Thanks! I guess this explains why most designers use an approach that proceeds very gradually from the known and proven to the unknown. If a design is significantly different from previous designs, you need to build it to assess its prospects in any empirical manner. I now understand how the NFA throttles development to a crawl, except for those willing to pay the SOT and deal with the bureaucracy associated with being a manufacturer.

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Re: Fluid Dynamics CAD Tools for Silencersmithing

Post by Bendersquint » Sat Jun 16, 2012 5:30 pm

calinb wrote:
Bendersquint wrote:For the most part yes, fluid dynamics can't accuratelly simulate gun powder gas flow.
Thanks! I guess this explains why most designers use an approach that proceeds very gradually from the known and proven to the unknown. If a design is significantly different from previous designs, you need to build it to assess its prospects in any empirical manner. I now understand how the NFA throttles development to a crawl, except for those willing to pay the SOT and deal with the bureaucracy associated with being a manufacturer.
What you are describing is a drawn out explanation of the term R&D.

Development hasn't been throttled to a crawl either, there is more development in this community than most other communities and more advancements as well.

You may not see all(or more likely ANY) of the development but it is rolling full steam ahead.

What the NFA does it forces improvement. If the NFA wasn't here we would have no better than European suppressor designs which are for the most part decaades behind US design and performance.

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Re: Fluid Dynamics CAD Tools for Silencersmithing

Post by Enfield577 » Sat Jun 16, 2012 6:17 pm

Bendersquint wrote: What you are describing is a drawn out explanation of the term R&D. Development hasn't been throttled to a crawl either, there is more development in this community than most other communities and more advancements as well. You may not see all(or more likely ANY) of the development but it is rolling full steam ahead. What the NFA does it forces improvement. If the NFA wasn't here we would have no better than European suppressor designs which are for the most part decaades behind US design and performance.
I am sure that is true, I am very greatful for the info that you guys are passing on but do wonder what is going on with the top manfacturers. How far will things move on is say 20 years time, quieter, smaller who knows
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Re: Fluid Dynamics CAD Tools for Silencersmithing

Post by Trex » Sat Jun 16, 2012 6:29 pm

Bendersquint wrote: What the NFA does it forces improvement. If the NFA wasn't here we would have no better than European suppressor designs which are for the most part decaades behind US design and performance.
I have seen you make this statement before - which leads me to be curious as to which UK, and other European makes and models of suppressors you have heard in person yourself?

If most of them are decades behind, in your experience which ones would be the equal (possibly better?) than the current US designs?

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Re: Fluid Dynamics CAD Tools for Silencersmithing

Post by Historian » Sun Jun 17, 2012 8:49 am

Trex wrote:
Bendersquint wrote: What the NFA does it forces improvement. If the NFA wasn't here we would have no better than European suppressor designs which are for the most part decaades behind US design and performance.
I have seen you make this statement before - which leads me to be curious as to which UK, and other European makes and models of suppressors you have heard in person yourself?

If most of them are decades behind, in your experience which ones would be the equal (possibly better?) than the current US designs?
With some research you might find information on the Chi-Com military replaceable silicone wipe design, interesting and informative for full auto.
Those who have purportedly seen and handled them have said to CZECH ( no slouches, either ) it out.

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Re: Fluid Dynamics CAD Tools for Silencersmithing

Post by doubloon » Sun Jun 17, 2012 10:21 am

There are papers out there on expanding gases of varying temperatures in a rarefied environment. Read burning gas cloud in space ...

I would think these would capture the essence of the problem. Gases of different temperatures expanding at different rates. The biggest difference probably being one of containment or lack thereof and the feedback in pressure from containment or partial containment.

Of course a silencer does not represent total containment (that's a bomb) but more so partial containment and the direction of pressure. The Dater Hole, the mouse hole, the baffle vent all being tools that "tune" pressures to optimize controlled release or partial containment of gasses.

All just theory of course, no actual practice.

ETA: I'm not sure why this problem wouldn't be similar to one of optimizing a rocket propulsion system. It seems like a suppressed shot would be similar in many aspects to a impulse propulsion system.
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Re: Fluid Dynamics CAD Tools for Silencersmithing

Post by calinb » Sun Jun 17, 2012 5:08 pm

Bendersquint wrote: What you are describing is a drawn out explanation of the term R&D.
It's a common description of research flying (flight test) in aviation. Yes. It applies to R&D in many industries--especially those that don't or can't use computers in any significant manner, or where the costs of a failure are very high, relative to a development "cycle."
Development hasn't been throttled to a crawl either, there is more development in this community than most other communities and more advancements as well.
<snip>
What the NFA does it forces improvement. If the NFA wasn't here we would have no better than European suppressor designs which are for the most part decaades behind US design and performance.
Firearms are far more popular as a sport and pastime in the U.S. than anywhere else. If firearms rights were not significantly infringed by the NFA (and all gun control since) and the Second Amendment was actually respected by our rulers, I'm sure developments would be forthcoming much more rapidly.

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