Anyone experiment making high and low pressure in cans?

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alidayvn
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Anyone experiment making high and low pressure in cans?

Post by alidayvn »

Maybe I should explain what I'm talking about. And since I've never seen this idea being used, is probably going to be tough for me to try to explain what I am thinking.

We know the sole duty of a suppressor and the relative theory in how they work.

What I am wondering about, is if anyone has ever experimented trying to make use of the pressure to have higher or lower pressures in a baffle, to perhaps direct the pressure to go a different direction other than forward and out of the can into the atmosphere, or away from the "normal flow" of the gas.

I believe the whole idea of porting or clipping in general is making use of directing pressure "flow".

But I was thinking about how one could perhaps direct more pressure back into a reflex portion of a can from within the expansion chamber, rather than just letting the natural expansion process move it back over the barrel.

*Especially since it's the highest pressure in a can, makes sense to use that pressure to do something, other than to simply exist as they do in most suppressor designs that I have ever seen. My whole idea is more directed, so it seems.

Here is a quick explanation to what's been rolling around in my head.

Use a ported muzzlebrake since they already port gas to the side rather than forward, and the expansion chamber be cone shaped so near where the bullet would exit from the brake, be narrow (should be a higher pressure because it is smaller diameter) and nearest the barrel, the larger portion of the cone, which should be a lower pressure because the expanding gas has more area, plus the whole volume of the reflex portion too.

Also, to explain something, the expansion chamber cone baffle would slide over the extreme front edge of the muzzlebrake and seat for a few reasons. 1. would be to help keep everything aligned, but mostly to seal off and block as much of the expansion chamber/ported gas from affecting the bullet path after it leaves that chamber.

I don't want a cone baffle directing the pressure onto the bullet affecting accuracy going into the next chamber, causing it to yaw or everything else, and why I was going to make the expansion cone butt up against the brake and essentially seal the expansion chamber from the rest of the baffles as much as I know how to.

I hope.

In my mind, the cone shape should direct some of the gas flow rearward and be more effective of filling the reflex portion. And thus, should also move a significant portion of the expanding gas away from leaving the suppressor and hopefully make the can more efficient and thus, quiet.

If there is another design like this out there, I am not aware of it. But I think it would work.

Whether it would be record-breaking or not; probably wouldn't be, but any improvement of efficiency is still an improvement nonetheless. I think we all have wanted to make the most quiet suppressor as possible by any means and this has been on my mind for years now. Along with a specifically shaped baffle that I am wanting to try along with this can.

If there is a similar design, I would be interested in learning more about it, and especially if I can find footage to hear what it sounds like.

So, here is a quick rough sketch of what I am trying to explain.

Hopefully between my vague explanation and rough sketch, may could get some opinions. Especially productive ones if there is some way to make it "better".
Historian
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Re: Anyone experiment making high and low pressure in cans?

Post by Historian »

You have hit upon a long ago set of ideas of fluid logic gates that
were once used in the 1960's in jet flows where a small side tunnel
passed pressure across the flow stream ... little pressure diverting
high speed.

Some parameters to think upon:

Caliber and can size that would benefit from this,
e.g., .223.

A .22 can being relatively low pressure in comparison is best
handled by length and baffle design. You could have seen this
effective simplicity in action in the sadly remove YouTube PTK
design ... estimated length about 10+", 1" I.D., ... K baffles.

(PTK, please repost for inspiration!)

Almost quieter than a pellet gun.

Consider researching Fluid-Logic Control on net.

You have many an exciting years ahead.

Best.
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Capt. Link.
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Re: Anyone experiment making high and low pressure in cans?

Post by Capt. Link. »

Sadly reflex areas in suppressors add the least amount of suppression but may help tune internal pressures to best suite a baffle type.Tubing passages within suppressors have been used in the past to dump gas into the rear of these "reflex" chambers to correct this deficiency.Just ask Dr Dater.

I'll share a Hi Low "idea" that I never got too in my studies. Imagine a baffle that uses aerodynamic shape to generate pressure differences. (like a planes wing profile) The bore hole could exhibit lower pressure due to baffle wall shape and the outer walls would be at higher pressure.
Let that stir a few brain cells with how these differences could be exploited.
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
ECCO Machine
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Re: Anyone experiment making high and low pressure in cans?

Post by ECCO Machine »

K baffles and Omega baffles both do what you're talking about with high and low pressure areas, but with limited effectiveness; I've achieved better suppression with conical baffles, including SPL reduction in production cans originally using Ks and Omegas like the SWR Trident and AAC Evolution.

A better way is an oversized tube with a post-core coaxial chamber. It's not gonna be something you can accomplish if you don't have respectable machining capabilities, but I've done this on more than one can which would have had too much volume for full diameter baffles to be efficient.

Image

Image

Image

The design works very well to reduce the uncorking pressure, thus lowering SPL.

That said, it's not really something that can be utilized with much effectiveness in high pressure, high velocity cartridge applications, and it requires having a tube volume that would be excessive for the application, ergo a larger, heavier can. If you're looking to keep dimensions & weight to a minimum, just use conical baffles with the correct profile, clip style and spacing for the application.
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3strucking
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Re: Anyone experiment making high and low pressure in cans?

Post by 3strucking »

The quality of your work is just amazing. I one day hope to be able to accomplish the same.
Historian
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Re: Anyone experiment making high and low pressure in cans?

Post by Historian »

May I ECCO 3strucking's admiration for the quality, design, and execution of your
machining and design skills.

It is at the 6-sigma level seen so long ago
demonstrated by tool and die maker mid-century machinists trained
in the 1920s.

They were given, at the beginning
of their apprenticeships, a large hunk of steel, a file, and a vise and
tasked with completing a perfect 1" x1" x 1" perfect cube by the
end of the term.

Machinists make engineers and designers look great.


Best.
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John A.
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Re: Anyone experiment making high and low pressure in cans?

Post by John A. »

alidayvn wrote: Mon Oct 14, 2019 2:00 am

Here is a quick explanation to what's been rolling around in my head.

Use a ported muzzlebrake since they already port gas to the side rather than forward, and the expansion chamber be cone shaped so near where the bullet would exit from the brake, be narrow (should be a higher pressure because it is smaller diameter) and nearest the barrel, the larger portion of the cone, which should be a lower pressure because the expanding gas has more area, plus the whole volume of the reflex portion too.

Also, to explain something, the expansion chamber cone baffle would slide over the extreme front edge of the muzzlebrake and seat for a few reasons. 1. would be to help keep everything aligned, but mostly to seal off and block as much of the expansion chamber/ported gas from affecting the bullet path after it leaves that chamber.

I don't want a cone baffle directing the pressure onto the bullet affecting accuracy going into the next chamber, causing it to yaw or everything else, and why I was going to make the expansion cone butt up against the brake and essentially seal the expansion chamber from the rest of the baffles as much as I know how to.

I hope.

In my mind, the cone shape should direct some of the gas flow rearward and be more effective of filling the reflex portion. And thus, should also move a significant portion of the expanding gas away from leaving the suppressor and hopefully make the can more efficient and thus, quiet.

If there is another design like this out there, I am not aware of it. But I think it would work.
There is a design out there exactly like what you are referring to. I did it several years ago on my blackout integral. Here's a photo of it before I put a round through it, and obviously the muzzlebrake and rear cap is not there so I could get a pic.

Image

Yes it works. I don't know how much because obviously I never heard it without it because that's how I built it but you can pack paper towels behind the ports into the reflex chamber and they're filthy after a single shot.

The design would work a lot better in a high pressure rifle round than a subsonic.
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SILENCERSTUDENT
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Re: Anyone experiment making high and low pressure in cans?

Post by SILENCERSTUDENT »

ECCO Machine wrote: Wed Oct 16, 2019 11:48 pm K baffles and Omega baffles both do what you're talking about with high and low pressure areas, but with limited effectiveness; I've achieved better suppression with conical baffles, including SPL reduction in production cans originally using Ks and Omegas like the SWR Trident and AAC Evolution.

A better way is an oversized tube with a post-core coaxial chamber. It's not gonna be something you can accomplish if you don't have respectable machining capabilities, but I've done this on more than one can which would have had too much volume for full diameter baffles to be efficient.

Image

Image

Image

The design works very well to reduce the uncorking pressure, thus lowering SPL.

That said, it's not really something that can be utilized with much effectiveness in high pressure, high velocity cartridge applications, and it requires having a tube volume that would be excessive for the application, ergo a larger, heavier can. If you're looking to keep dimensions & weight to a minimum, just use conical baffles with the correct profile, clip style and spacing for the application.
i didnt ask the last time u shared these but im curious about the inner and outer diameters of the inner and outer tubes.. approximate is fine if u dont remeber. so cool
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Re: Anyone experiment making high and low pressure in cans?

Post by ECCO Machine »

SILENCERSTUDENT wrote: Mon Oct 28, 2019 3:05 pm

i didnt ask the last time u shared these but im curious about the inner and outer diameters of the inner and outer tubes.. approximate is fine if u dont remeber. so cool
The 9mm was a 1.75" OD .054" wall with 1.25" .035" wall inner tube.

The 6" rimfire can is a 1.512" OD that was .080" wall, but I thinned it out to .040" between the threads. The inner tube is 1.000" OD .020" wall.

The other one was awhile ago, but if memory serves, that big honkin' aluminum tube was 1.75" ID. The inner tube on that one I did anodized 6061-T651 tube, 1.062" OD 1/16" wall
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Capt. Link.
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Re: Anyone experiment making high and low pressure in cans?

Post by Capt. Link. »

Image
Image
Image


Flawless is a understatement!

I'm a huge fan of the coaxial design.
Do you lock the bolt back before firing the Two Two. :D :D
The only reason after 243 years the government now wants to disarm you is they intend to do something you would shoot them for!
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Ridge Runner
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Re: Anyone experiment making high and low pressure in cans?

Post by Ridge Runner »

Looking at the images above has me wondering.
1. Is that a ~2" barrel or is it a ~6" thoroughly ported barrel?
2. What sort of muzzle velocity are you getting and with what ammo?
3. What tricks are you using to get the 10/22 to cycle or are you manually cycling?
4. If you are manually cycling, how are you locking the bolt to avoid jams?

Really something of a work of art. Correct me if my assumption that is a Ruger 10/22 or Charger build.

I put a 4 1/2" barrel on a Ruger Charger Pistol and am getting ~980 fps with standard ~1260 fps bulk ammo. Very pleased with the ballistic performance but the thing jams every few rounds. Trying to figure out a solution.

I should be able to mount a suppressor on it in 6 to 8 weeks assuming my form 1 gets approved in 3-4 weeks. Is there a reasonable chance adding the suppressor will improve the cycling situation, or should I be looking for ways to lighten the bolt or soften the charging spring?
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Capt. Link.
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Re: Anyone experiment making high and low pressure in cans?

Post by Capt. Link. »

Ridge Runner wrote: Tue Apr 07, 2020 12:24 am
I put a 4 1/2" barrel on a Ruger Charger Pistol and am getting ~980 fps with standard ~1260 fps bulk ammo. Very pleased with the ballistic performance but the thing jams every few rounds. Trying to figure out a solution.

should I be looking for ways to lighten the bolt or soften the charging spring?
Ecco's coaxial suppressor is a work of art indeed.
The Ruger action in rifle or pistol can be made to work flawlessly with a 2.00" barrel without a lightened spring or bolt even running subsonic ammo. This is basic information for the normal culprits.
The ejector and magazine can cause failure to eject.
The chamber and extractor can cause extraction issues and failure to feed.
The bolt and fire control group can contribute to extraction,feed,ejection and ignition problems.

I rework the whole action including the chamber to make these run without a hitch.
I would never lighten the bolt or the spring as its not required and may make the action less reliable with some ammo.
I'm a retired smith but always willing to help the community.
-CL
The only reason after 243 years the government now wants to disarm you is they intend to do something you would shoot them for!
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Zero99z
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Re: Anyone experiment making high and low pressure in cans?

Post by Zero99z »

I'm experimenting with this, trying to increase dwell time of the gas in the can. I'm taking a bit of an unconventional approach. It's kinda like a reflex can, except the blast chamber is a larger diameter, with the main tube recessed into it. It mounts onto a brake and the blast baffle divides the blast chamber. There will be a secondary blast baffle on the main tube that acts as a "gas stripper" to keep the gases out of the main tube. No idea how well it'll work yet.
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John A.
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Re: Anyone experiment making high and low pressure in cans?

Post by John A. »

Only one way to find out :D
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Zero99z
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Re: Anyone experiment making high and low pressure in cans?

Post by Zero99z »

It's a special purpose can for my 50bmg. I more so want recoil reduction than sound suppression.
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John A.
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Re: Anyone experiment making high and low pressure in cans?

Post by John A. »

I started a topic similar to this 4 years ago. It's even titled about the same.

viewtopic.php?f=10&t=137484
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fishman
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Re: Anyone experiment making high and low pressure in cans?

Post by fishman »

John A. wrote: Sat Apr 11, 2020 8:57 am I started a topic similar to this 4 years ago. It's even titled about the same.

viewtopic.php?f=10&t=137484
When I saw the thread title, I thought it was the same thread
300 blackout form 1: http://www.silencertalk.com/forum/viewtopic.php?f=10&t=137293

5.56 form 1:
http://www.silencertalk.com/forum/viewtopic.php?f=10&t=141800&p=955647#p955647
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Re: Anyone experiment making high and low pressure in cans?

Post by SILENCERSTUDENT »

See elevated silence bc design, they segment the ports of a brake into there own individual chambers and then run them forward coaxially for an inch or two
WalkerGHarris
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Re: Anyone experiment making high and low pressure in cans?

Post by WalkerGHarris »

https://youtu.be/S341CDvbY8Q

Here is a company saying they have done what you are talking about

Creating low pressure zones to draw the high pressure into separate chambers.

NG2 Defense
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John A.
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Re: Anyone experiment making high and low pressure in cans?

Post by John A. »

In looking at that silencer cutaway, the just made a monocore baffle between baffles.

And I'm not saying it won't work, but makes you wonder why the military are not using their suppressors.
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